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[Type here] 
 
Types of Test Cases: 
 
Unit Testing 
Unit testing verifies a single function or method in isolation to ensure it works correctly. 
  Example: Testing one function’s logic without database, API, or UI. 
 
Integration Testing 
Integration testing verifies multiple functions or modules working together, where one function may call another 
function or interact with external components like a database.


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Example: Testing a function that internally calls another function and processes combined results. 
 
Functional Testing 
Functional testing verifies the complete feature or page behavior, ensuring the system performs as expected from 
the user’s perspective. 
  Example: Testing a full page or API endpoint that processes user input and returns output. 
 
 
SpringBoot Test Cases: 
 
References (BEST LEARNING LINKS) 
     Official Docs 
   Spring Boot Testing


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Official Docs 
   Spring Boot Testing 
https://docs.spring.io/spring-boot/docs/current/reference/html/features.html#features.testing 
     Baeldung (Highly Recommended) 
   Controller Testing 
https://www.baeldung.com/spring-boot-testing 
   MockMvc 
https://www.baeldung.com/spring-mvc-test-examples 
          YouTube (Easy) 
• Search: “Spring Boot MockMvc tutorial” 
• Channel: Java Brains / Amigoscode 
Recommended Approach for LMS Project  [Type here] 
 
Layer Testing Tool Notes


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Layer Testing Tool Notes 
Controller / API MockMvc Fast, mock dependencies 
Service JUnit + Mockito Test business logic without HTTP 
Repository @DataJpaTest Test DB queries with H2 
Full App Flow @SpringBootTest End-to-end integration 
 
Unit Test Cases 
 
╔════════════════════════════════════════════════════════════
══════════════════╗ 
║                    CONTROLLER TESTING QUICK REFERENCE                        ║ 
╚════════════════════════════════════════════════════════════


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══════════════════╝ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 1. TEST CLASS SETUP                                                          │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
@ExtendWith(MockitoExtension.class)  ← Add this to every test class 
class YourControllerTest { 
     
    @Mock                                ← Fake version of dependency 
    private YourService service;


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private YourService service; 
     
    @InjectMocks                         ← Real controller with fake dependencies 
    private YourController controller; 
     
    @Test                                ← This marks a test method 
    void testSomething() { } 
} 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 2. THE AAA PATTERN (Use in Every Test)                                      │  [Type here]


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└──────────────────────────────────────────────────────────────────────────────┘ 
 
@Test 
void testMethod_Success() { 
     
    // ===== ARRANGE ===== (Set up) 
    when(service.getData()).thenReturn(data); 
     
    // ===== ACT ===== (Execute) 
    ResponseEntity<?> response = controller.method(); 
     
    // ===== ASSERT ===== (Check) 
    assertEquals(HttpStatus.OK, response.getStatusCode()); 
     
    // ===== VERIFY ===== (Confirm method calls)


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// ===== VERIFY ===== (Confirm method calls) 
    verify(service, times(1)).getData(); 
} 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 3. MOCKITO PATTERNS                                                          │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌─────────────────────────────┬──────────────────────────────────────────────┐


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│ Pattern                     │ When to Use                                  │ 
├─────────────────────────────┼──────────────────────────────────────────────┤ 
│ when().thenReturn()         │ Method returns a value                       │ 
│ when().thenThrow()          │ Method throws exception                      │ 
│ doNothing().when()          │ Method returns void                          │ 
│ any()                       │ Any argument of any type                     │


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│ anyLong()                   │ Any Long argument                            │ 
│ anyString()                 │ Any String argument                          │  [Type here] 
 
│ eq(value)                   │ Specific value (with any())                  │ 
└─────────────────────────────┴──────────────────────────────────────────────┘ 
 
Examples: 
┌──────────────────────────────────────────────────────────────────────────────┐


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│ when(service.findById(1L)).thenReturn(user);                                 │ 
│ when(service.findById(any())).thenReturn(user);                              │ 
│ when(service.save(any())).thenThrow(new RuntimeException());                 │ 
│ doNothing().when(service).delete(1L);                                        │ 
│ when(service.update(eq(1L), any())).thenReturn(updated);                     │ 
└──────────────────────────────────────────────────────────────────────────────┘


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┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 4. COMMON ASSERTIONS                                                         │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌─────────────────────────────────────┬────────────────────────────────────────┐ 
│ Assertion                           │ What it Checks                         │ 
├─────────────────────────────────────┼────────────────────────────────────────┤


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│ assertEquals(expected, actual)      │ Two values are equal                   │ 
│ assertNotNull(object)               │ Object is not null                     │ 
│ assertTrue(condition)               │ Condition is true                      │ 
│ assertFalse(condition)              │ Condition is false                     │ 
│ assertThrows(Exception.class, ...)  │ Code throws exception                  │ 
└─────────────────────────────────────┴────────────────────────────────────────┘


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Examples: 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ assertEquals(HttpStatus.OK, response.getStatusCode());                       │ 
│ assertNotNull(response.getBody());                                           │ 
│ assertEquals("John", user.getName());                                        │  [Type here] 
 
│ assertTrue(list.isEmpty());                                                  │


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└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 5. VERIFY METHOD CALLS                                                       │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ verify(service, times(1)).method();     ← Called exactly once                │


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│ verify(service, times(2)).method();     ← Called exactly twice               │ 
│ verify(service, never()).method();      ← Never called                       │ 
│ verify(service, atLeast(1)).method();   ← Called at least once               │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 6. TEST SCENARIOS (Write These for Every Method)                            │


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└──────────────────────────────────────────────────────────────────────────────┘ 
 
For a GET method: 
├──    testGetMethod_Success          (Returns 200 OK with data) 
├──    testGetMethod_NotFound         (Returns 404 when not found) 
├──    testGetMethod_Error            (Returns 500 on exception) 
└──    testGetMethod_EmptyData        (Returns 200 with empty list) 
 
For a POST method: 
├──    testPostMethod_Success         (Returns 201 CREATED)


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├──    testPostMethod_BadRequest      (Returns 400 for invalid data) 
├──    testPostMethod_Error           (Returns 500 on exception) 
└──    testPostMethod_Duplicate       (Returns 409 if already exists) 
 
For a DELETE method:  [Type here] 
 
├──    testDeleteMethod_Success       (Returns 200 OK) 
├──    testDeleteMethod_NotFound      (Returns 404) 
└──    testDeleteMethod_Error         (Returns 500 on exception)


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┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 7. RUNNING TESTS                                                             │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
Command Line: 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ mvn test                              ← Run all tests                        │


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│ mvn test -Dtest=YourControllerTest    ← Run specific test class             │ 
│ mvn test -Dtest=YourControllerTest#testMethod  ← Run specific test method   │ 
│ mvn clean test jacoco:report          ← Run with coverage report            │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
IDE: 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ Right-click test file → Run 'YourControllerTest'                            │


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│ Right-click test method → Run 'testMethod'                                  │ 
│ Click green play button next to test                                        │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 8. TEST NAMING CONVENTION                                                    │ 
└──────────────────────────────────────────────────────────────────────────────┘


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Format: test[MethodName]_[Scenario] 
 
Examples: 
├── testGetUser_Success  [Type here] 
 
├── testGetUser_NotFound 
├── testGetUser_Error 
├── testCreateUser_Success 
├── testCreateUser_ValidationError 
├── testDeleteUser_Success 
└── testDeleteUser_NotFound 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 9. COMPLETE EXAMPLE                                                          │


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└──────────────────────────────────────────────────────────────────────────────┘ 
 
Controller: 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ @GetMapping("/user/{id}")                                                    │ 
│ public ResponseEntity<User> getUser(@PathVariable Long id) {                │ 
│     User user = userService.findById(id);                                   │


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│     return ResponseEntity.ok(user);                                         │ 
│ }                                                                            │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
Test: 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ @ExtendWith(MockitoExtension.class)                                         │ 
│ class UserControllerTest {                                                  │


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│                                                                              │ 
│     @Mock                                                                    │ 
│     private UserService userService;                                        │ 
│                                                                              │ 
│     @InjectMocks                                                             │ 
│     private UserController userController;                                  │


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│                                                                              │  [Type here] 
 
│     @Test                                                                    │ 
│     void testGetUser_Success() {                                            │ 
│         // ARRANGE                                                           │ 
│         Long userId = 1L;                                                    │


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│         User expectedUser = new User(1L, "John");                           │ 
│         when(userService.findById(userId)).thenReturn(expectedUser);        │ 
│                                                                              │ 
│         // ACT                                                               │ 
│         ResponseEntity<User> response = userController.getUser(userId);     │ 
│                                                                              │


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│         // ASSERT                                                            │ 
│         assertEquals(HttpStatus.OK, response.getStatusCode());              │ 
│         assertEquals("John", response.getBody().getName());                 │ 
│                                                                              │ 
│         // VERIFY                                                            │ 
│         verify(userService, times(1)).findById(userId);                     │


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│     }                                                                        │ 
│ }                                                                            │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 10. TROUBLESHOOTING                                                          │ 
└──────────────────────────────────────────────────────────────────────────────┘


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Problem: Mocks don't work 
└── Solution: Add @ExtendWith(MockitoExtension.class) 
 
Problem: NullPointerException in test 
└── Solution: Did you mock the return value? when(service.method()).thenReturn(...) 
 
Problem: Test fails with "wanted but not invoked"  [Type here] 
 
└── Solution: Check if method name and parameters match exactly 
 
Problem: Wrong number of invocations 
└── Solution: Check verify() count matches actual method calls 
 
Problem: Can't use eq() and any() together


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Problem: Can't use eq() and any() together 
└── Solution: If you use any() for one parameter, use eq() for specific values 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 11. CHECKLIST BEFORE SUBMITTING TESTS                                       │ 
└──────────────────────────────────────────────────────────────────────────────┘ 
 
□ Test class has @ExtendWith(MockitoExtension.class) 
□ All dependencies are mocked with @Mock


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□ All dependencies are mocked with @Mock 
□ Controller has @InjectMocks 
□ Success test case written 
□ Error test case written 
□ Edge cases covered 
□ All tests use AAA pattern 
□ Tests have descriptive names 
□ verify() statements added where needed 
□ All tests pass: mvn test 
□ No System.out.println() in tests 
 
┌──────────────────────────────────────────────────────────────────────────────┐ 
│ 12. REMEMBER                                                                 │


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└──────────────────────────────────────────────────────────────────────────────┘ 
 
       One test = One scenario 
          AAA Pattern = Arrange, Act, Assert 
   Mock = Fake object  [Type here] 
 
   Verify = Check method was called 
    Test success AND failure scenarios 
        Start simple, add complexity gradually 
 
Integration Test cases: 
 
File Placement 
1. Test Class 
src/test/java/com/britanica/pbl/controller/ 
└── DomainControllerIntegrationTest.java 
2. Test Configuration


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2. Test Configuration 
src/test/resources/ 
└── application-test.properties 
 
Step 1: Add H2 Database Dependency 
Add to your pom.xml: 
    <!-- H2 Database for Testing --> 
    <dependency> 
        <groupId>com.h2database</groupId> 
        <artifactId>h2</artifactId> 
        <scope>test</scope> 
    </dependency> 
 
Run All Integration Tests 
mvn test -Dtest=DomainControllerIntegrationTest 
 
Sample Example: 
  [Type here] 
 
@SpringBootTest                 // ← Loads full Spring context


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@AutoConfigureMockMvc          // ← Provides MockMvc for HTTP testing 
@Transactional                 // ← Rollback after each test 
class DomainControllerIntegrationTest { 
     
    @Autowired 
    private MockMvc mockMvc;            // ← Simulates HTTP requests 
     
    @Autowired 
    private DomainRepository repository; // ← Real repository 
     
    @Test 
    @WithMockUser(authorities = "Admin") // ← Mock security 
    void testListDomains_Success() throws Exception {


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// Insert REAL data into database 
        Domain domain = new Domain(); 
        domain.setDomainName("Test"); 
        repository.save(domain);  // ← Actually saves to H2 database 
         
        // Make REAL HTTP request 
        mockMvc.perform(get("/domain/list")) 
            .andExpect(status().isOk()) 
            .andExpect(jsonPath("$.domain", hasSize(1))); 
    } 
} 
 
MockMvc Request Patterns 
GET Request  [Type here] 
 
java 
mockMvc.perform(get("/domain/list")


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java 
mockMvc.perform(get("/domain/list") 
        .param("page", "0") 
        .param("size", "10") 
        .param("search", "test") 
        .contentType(MediaType.APPLICATION_JSON)) 
    .andExpect(status().isOk()) 
    .andExpect(jsonPath("$.domain").isArray()); 
POST Request 
java 
mockMvc.perform(post("/domain/create") 
        .contentType(MediaType.APPLICATION_JSON) 
        .content(jsonString)) 
    .andExpect(status().isCreated())


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.andExpect(status().isCreated()) 
    .andExpect(jsonPath("$.error").value("false")); 
PUT Request 
java 
mockMvc.perform(put("/domain/update") 
        .contentType(MediaType.APPLICATION_JSON) 
        .content(jsonString)) 
    .andExpect(status().isOk()); 
DELETE Request 
java 
mockMvc.perform(delete("/domain/delete/{id}", domainId) 
        .contentType(MediaType.APPLICATION_JSON)) 
    .andExpect(status().isOk()); 
 
    Common JSON Path Expressions 
java 
// Check string value


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java 
// Check string value 
.andExpect(jsonPath("$.error").value("false"))  [Type here] 
 
 
// Check boolean 
.andExpect(jsonPath("$.error").value(false)) 
 
// Check number 
.andExpect(jsonPath("$.totalElements").value(10)) 
 
// Check array size 
.andExpect(jsonPath("$.domain", hasSize(5))) 
 
// Check array exists 
.andExpect(jsonPath("$.domain").isArray()) 
 
// Check nested value 
.andExpect(jsonPath("$.domain[0].domainName").value("Test")) 
 
// Check exists


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// Check exists 
.andExpect(jsonPath("$.message").exists()) 
 
// Check doesn't exist 
.andExpect(jsonPath("$.error").doesNotExist()) 
 
// Check not null 
.andExpect(jsonPath("$.domain").isNotEmpty())


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PHP 
i 
 
 
About the T utorial 
The PHP Hypertext Preprocessor (PHP) is a programming language that allows web 
developers to create dynamic content that interacts with databases. PHP is basically used 
for developing web-based software applications. This tutorial will help you understand the 
basics of PHP and how to put it in practice. 
 
Audience 
This tutorial has been designed to meet the requirements of all those readers who are 
keen to learn the basics of PHP.


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keen to learn the basics of PHP.   
 
Prerequisites 
Before proceeding with this tutorial, you should have a basic understanding of computer 
programming, Internet, Database, and MySQL. 
 
Copyright & Disclaimer 
© Copyright 2016 by Tutorials Point (I) Pvt. Ltd.  
 
All the content and graphics published in this e-book are the property of Tutorials Point (I) 
Pvt. Ltd.  The user of this e-book is prohibited to reuse, retain, copy, distribute or republish


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any contents or a part of contents of this e -book in any manner without written consent 
of the publisher.   
 
We strive to update the contents of our website and tutorials as timely and as precisely as 
possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. 
Ltd. provides no guarantee regarding the accuracy, timeliness o r completeness of our 
website or its contents including this tutorial. If you discover any errors on our website or


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in this tutorial, please notify us at contact@tutorialspoint.com 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    PHP 
ii 
 
 
T able of Contents 
About the Tutorial ............................................................................................................................................ i 
Audience ........................................................................................................................................................... i


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Prerequisites ..................................................................................................................................................... i 
Copyright & Disclaimer ..................................................................................................................................... i 
Table of Contents ............................................................................................................................................ ii


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PART 1: LEARNING PHP ................................ ................................ ................................ ............... 1 
 PHP ─ Introduction .................................................................................................................................... 2 
Common Uses of PHP ...................................................................................................................................... 2


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Characteristics of PHP ..................................................................................................................................... 3 
"Hello World" Script in PHP ............................................................................................................................. 3 
 PHP ─ Environment Setup ......................................................................................................................... 4


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PHP Parser Installation .................................................................................................................................... 4 
PHP Installation on Linux or Unix with Apache ............................................................................................... 4 
PHP Installation on Mac OS X with Apache ..................................................................................................... 6


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PHP Installation on Windows NT/2000/XP with IIS ......................................................................................... 7 
PHP Installation on Windows NT/2000/XP with Apache ................................................................................. 8 
Apache Configuration for PHP ....................................................................................................................... 10


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PHP.INI file Configuration .............................................................................................................................. 11 
 PHP ─ Syntax Overview ........................................................................................................................... 15 
Escaping to PHP ............................................................................................................................................. 15


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Commenting PHP Code ................................................................................................................................. 16 
PHP is whitespace insensitive ........................................................................................................................ 16 
PHP is case sensitive ...................................................................................................................................... 17


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Statements are expressions terminated by semicolons ................................................................................ 17 
Expressions are combinations of tokens ....................................................................................................... 17 
Braces make blocks ....................................................................................................................................... 17


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Running PHP Script from Command Prompt ................................................................................................. 18 
 PHP ─ Variable Types .............................................................................................................................. 19 
Integers .......................................................................................................................................................... 20


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Doubles .......................................................................................................................................................... 20 
Boolean .......................................................................................................................................................... 20


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NULL .............................................................................................................................................................. 21 
Strings ............................................................................................................................................................ 21 
Variable Naming ............................................................................................................................................ 24


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PHP – Variables .............................................................................................................................................. 24 
PHP Local Variables ....................................................................................................................................... 24 
PHP Function Parameters .............................................................................................................................. 25


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PHP Global Variables ..................................................................................................................................... 25 
PHP Static Variables ....................................................................................................................................... 26 
 PHP ─ Constants ...................................................................................................................................... 27


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PHP ─ Operator Types ............................................................................................................................. 29 
Arithmetic Operators..................................................................................................................................... 29    PHP 
iii 
 
Comparison Operators .................................................................................................................................. 31


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Logical Operators ........................................................................................................................................... 33 
Assignment Operators ................................................................................................................................... 35 
Conditional Operator ..................................................................................................................................... 37


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Operators Categories .................................................................................................................................... 38 
Precedence of PHP Operators ....................................................................................................................... 38 
 PHP ─ Decision Making ........................................................................................................................... 40


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The If...Else Statement................................................................................................................................... 40 
The ElseIf Statement...................................................................................................................................... 41 
The Switch Statement ................................................................................................................................... 42


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PHP ─ Loop Types .................................................................................................................................... 45 
The for loop statement .................................................................................................................................. 45 
The while loop statement .............................................................................................................................. 46


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The do...while loop statement ...................................................................................................................... 47 
The foreach loop statement .......................................................................................................................... 48 
The break statement ..................................................................................................................................... 48


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The continue statement ................................................................................................................................ 50 
 PHP ─ Arrays ........................................................................................................................................... 52 
Numeric Array ............................................................................................................................................... 52


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Associative Arrays .......................................................................................................................................... 53 
Multidimensional Arrays ............................................................................................................................... 54 
 PHP ─ Strings ........................................................................................................................................... 57


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String Concatenation Operator ..................................................................................................................... 58 
Using the strlen() function ............................................................................................................................. 58 
Using the strpos() function ............................................................................................................................ 59


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PHP ─ Web Concepts ............................................................................................................................... 60 
Identifying Browser & Platform ..................................................................................................................... 60 
Display Images Randomly .............................................................................................................................. 61


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Using HTML Forms ......................................................................................................................................... 62 
Browser Redirection ...................................................................................................................................... 63 
Displaying "File Download" Dialog Box ......................................................................................................... 64


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PHP ─ GET and POST Methods ................................................................................................................ 66 
The GET Method ............................................................................................................................................ 66 
The POST Method .......................................................................................................................................... 67


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The $_REQUEST variable ............................................................................................................................... 68 
 PHp ─ File Inclusion ................................................................................................................................. 70 
The include() Function ................................................................................................................................... 70


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The require() Function ................................................................................................................................... 71 
 PHP ─ Files & I/O ..................................................................................................................................... 72 
Opening and Closing Files .............................................................................................................................. 72


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Reading a file ................................................................................................................................................. 73 
Writing a File ................................................................................................................................................. 74 
 PHP ─ Functions ...................................................................................................................................... 76


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Creating PHP Function ................................................................................................................................... 76 
PHP Functions with Parameters .................................................................................................................... 77 
Passing Arguments by Reference .................................................................................................................. 77    PHP 
iv


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iv 
 
PHP Functions returning value ...................................................................................................................... 78 
Setting Default Values for Function Parameters ........................................................................................... 79 
Dynamic Function Calls .................................................................................................................................. 80


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PHP ─ Cookies ......................................................................................................................................... 81 
The Anatomy of a Cookie .............................................................................................................................. 81 
Setting Cookies with PHP............................................................................................................................... 82


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Accessing Cookies with PHP .......................................................................................................................... 83 
Deleting Cookie with PHP .............................................................................................................................. 84 
 PHP ─ Sessions ........................................................................................................................................ 85


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Starting a PHP Session ................................................................................................................................... 85 
Destroying a PHP Session .............................................................................................................................. 87 
Turning on Auto Session ................................................................................................................................ 87


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Sessions without cookies ............................................................................................................................... 87 
 PHP ─ Sending Emails .............................................................................................................................. 89 
Sending plain text email ................................................................................................................................ 89


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Sending HTML email ...................................................................................................................................... 91 
Sending attachments with email ................................................................................................................... 92 
 PHP ─ File Uploading ............................................................................................................................... 95


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Creating an Upload Form .............................................................................................................................. 95 
Creating an upload script .............................................................................................................................. 96 
 PHP ─ Coding Standard ........................................................................................................................... 98


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PART 2: ADVANCED PHP ................................ ................................ ................................ ......... 101 
 PHP ─ Predefined Variables ................................................................................................................... 102 
PHP Superglobals ......................................................................................................................................... 102


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Server variables: $_SERVER ......................................................................................................................... 103 
 PHP ─ Regular Expression ...................................................................................................................... 106 
POSIX Regular Expressions .......................................................................................................................... 106


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PHP's Regexp POSIX Functions .................................................................................................................... 108 
PHP ─ Function ereg() .................................................................................................................................. 108 
PHP ─ Function ereg_replace() .................................................................................................................... 110


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PHP ─ Function eregi() ................................................................................................................................. 111 
PHP ─ Function eregi_replace() ................................................................................................................... 112 
PHP ─ Function split() .................................................................................................................................. 113


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PHP ─ Function spliti() ................................................................................................................................. 114 
PHP ─ Function sql_regcase() ...................................................................................................................... 115 
PERL Style Regular Expressions ................................................................................................................... 115


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PHP's Regexp PERL Compatible Functions .................................................................................................. 117 
PHP ─ Function preg_match() ...................................................................................................................... 117 
PHP ─ Function preg_match_all() ................................................................................................................ 118


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PHP ─ Function preg_replace() .................................................................................................................... 119 
PHP ─ Function preg_split() ......................................................................................................................... 120 
PHP ─ Function preg_grep() ........................................................................................................................ 121


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PHP ─ Function preg_quote() ...................................................................................................................... 122 
 PHP ─ Error and Exception Handling...................................................................................................... 124 
Using die() function ..................................................................................................................................... 124    PHP 
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v 
 
Defining Custom Error Handling Function ................................................................................................... 124 
Exceptions Handling .................................................................................................................................... 127 
 PHP ─ Bugs Debugging .......................................................................................................................... 129


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PHP ─ Date and Time ............................................................................................................................ 131 
Getting the Time Stamp with time() ............................................................................................................ 131 
Converting a Time Stamp with getdate() .................................................................................................... 131


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Converting a Time Stamp with date() .......................................................................................................... 133 
 PHP ─ PHP and MySQL .......................................................................................................................... 136 
What you should already have? .................................................................................................................. 136


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Connecting to MySQL Database .................................................................................................................. 137 
Create MySQL Database Using PHP ............................................................................................................. 138 
Delete MySQL Database Using PHP ............................................................................................................. 143


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Insert Data to MySQL Database .................................................................................................................. 144 
Retrieving Data from MySQL Database ....................................................................................................... 148 
Using Paging through PHP ........................................................................................................................... 152


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Updating Data into MySQL Database .......................................................................................................... 154 
Deleting Data from MySQL Database .......................................................................................................... 157 
Using PHP to Backup MySQL Database ....................................................................................................... 159


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PHP ─ PHP and AJAX ............................................................................................................................. 162 
What is AJAX ? ............................................................................................................................................. 162 
PHP and AJAX Example ................................................................................................................................ 162


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Client Side HTML file.................................................................................................................................... 163 
Server Side PHP file ..................................................................................................................................... 165 
 PHP ─ PHP and XML .............................................................................................................................. 167


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HTML list that's not valid XML ..................................................................................................................... 167 
HTML list that is valid XML .......................................................................................................................... 167 
Parsing an XML Document .......................................................................................................................... 167


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Generating an XML Document .................................................................................................................... 169 
 PHP ─ Object Oriented Programming .................................................................................................... 170 
Object Oriented Concepts ........................................................................................................................... 170


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Defining PHP Classes ................................................................................................................................... 171 
Creating Objects in PHP ............................................................................................................................... 172 
Calling Member Functions ........................................................................................................................... 172


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Constructor Functions ................................................................................................................................. 173 
Destructor .................................................................................................................................................... 174 
Inheritance .................................................................................................................................................. 174


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Function Overriding ..................................................................................................................................... 175 
Public Members ........................................................................................................................................... 175 
Private members ......................................................................................................................................... 175


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Protected members ..................................................................................................................................... 176 
Interfaces ..................................................................................................................................................... 177 
Constants ..................................................................................................................................................... 177


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Abstract Classes ........................................................................................................................................... 177 
Static Keyword ............................................................................................................................................. 178 
Final Keyword .............................................................................................................................................. 178


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PHP ─ PHP for C Developers .................................................................................................................. 181 
Similarities ................................................................................................................................................... 181 
Differences .................................................................................................................................................. 181    PHP 
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vi 
 
 PHP ─ PHP for PERL Developers ............................................................................................................ 183 
Similarities ................................................................................................................................................... 183 
Differences .................................................................................................................................................. 183


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PART 3: FUNCTION REFERENCE................................ ................................ ...............................  185 
 PHP ─ Function Reference ..................................................................................................................... 186    PHP 
7 
 
Part 1: Learning PHP    PHP 
8 
 
PHP started out as a small open source project that evolved as more and more people found


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out how useful it was. Rasmus Lerdorf unleashed the first version of PHP way back in 1994.  
 
 PHP is a recursive acronym for "PHP: Hypertext Preprocessor". 
 
 PHP is a server side scripting language that is embedded in HTML. It is used to manage 
dynamic content, databases, session tracking, even build entire e-commerce sites. 
 
 It is integrated with a number of popular databases, including MySQL, PostgreSQL, 
Oracle, Sybase, Informix, and Microsoft SQL Server.


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 PHP is pleasingly zippy in its execution, especially when compiled as an Apache module 
on the Unix side. The MySQL server, once started, executes even very complex queries 
with huge result sets in record-setting time. 
 
 PHP supports a large number of major protocols such as POP3, IMAP, and LDAP. PHP4 
added support for Java and distributed object architectures (COM and CORBA), making 
n-tier development a possibility for the first time.


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 PHP is forgiving: PHP language tries to be as forgiving as possible. 
 
 PHP Syntax is C-Like. 
Common Uses of PHP 
PHP performs system functions, i.e. from files on a system it can create, open, read, write, 
and close them. The other uses of PHP are:  
 
 PHP can handle forms, i.e. gather data from files, save data  to a file, thru email you 
can send data, return data to the user. 
 
 You add, delete, modify elements within your database thru PHP.


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 Access cookies variables and set cookies. 
 
 Using PHP, you can restrict users to access some pages of your website. 
 
 It can encrypt data. 
 
 
 
 
  
 PHP ─ INTRODUCTION    PHP 
9 
 
Characteristics of PHP 
Five important characteristics make PHP's practical nature possible: 
 
 Simplicity 
 
 Efficiency 
 
 Security 
 
 Flexibility 
 
 Familiarity 
"Hello World" Script in PHP 
To get a feel of PHP, first start with simple PHP scripts. Since "Hello, World!" is an essential


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example, first we will create a friendly little "Hello, World!" script. 
 
As mentioned earlier, PHP is embedded in HTML. That means that in amongst your normal 
HTML (or XHTML if you're cutting-edge) you'll have PHP statements like this: 
<html> 
<head> 
<title>Hello World</title> 
<body> 
    <?php echo "Hello, World!";?> 
</body> 
</html> 
It will produce the following result: 
Hello, World! 
If you examine the HTML output of the above example, you'll notice that the PHP code is not


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present in the file sent from the server to your Web browser. All of the PHP present in the 
Web page is processed and stripped from the page; the only thing returned to the client from 
the Web server is pure HTML output. 
 
All PHP code must be included inside one of the three special markup tags ate are recognized 
by the PHP Parser. 
<?php PHP code goes here ?> 
 
<?    PHP code goes here ?> 
 
<script language="php"> PHP code goes here </script>


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Most common tag is the <?php...?> and we will also use the same tag in our tutorial.    PHP 
10 
 
 
From the next chapter, we will start with PHP Environment Setup on your machine and then 
we will dig out almost all concepts related to PHP to make you comfortable with t he PHP 
language.    PHP 
11 
 
In order to develop and run PHP Web pages , three vital components need to be installed on 
your computer system.


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your computer system. 
 
Web Server - PHP will work with virtually all Web Server software, including Microsoft's 
Internet Information Server (IIS) but then most often used is freely available Apache Server. 
Download Apache for free here: http://httpd.apache.org/download.cgi 
 
Database - PHP will work with virtually all database software, including Oracle and Sybase 
but most commonly used is freely available MySQL database. Download MySQL for free here:


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http://www.mysql.com/downloads/index.html 
 
PHP Parser  - In order to process PHP script instructions , a parser must be installed to 
generate HTML output that can be sent to the Web Browser. This tutorial will guide you how 
to install PHP parser on your computer. 
PHP Parser Installation 
Before you proceed, it is important to make sure that you have a proper environment setup 
on your machine to develop your web programs using PHP.


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Type the following address into your browser's address box. 
http://127.0.0.1/info.php 
If this displays a  page showing your PHP installation related information , then it means you 
have PHP and Webserver installed properly. Otherwise you have to follow given procedure to 
install PHP on your computer. 
 
This section will guide you to install and configure PHP over the following four platforms: 
 PHP Installation on Linux or Unix with Apache 
 PHP Installation on Mac OS X with Apache


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 PHP Installation on Mac OS X with Apache 
 PHP Installation on Windows NT/2000/XP with IIS 
 PHP Installation on Windows NT/2000/XP with Apache 
PHP Installation on Linux or Unix with Apache 
If you plan to install PHP on Linux or any other variant of Unix, then here is the list of 
prerequisites: 
 
 PHP ─ ENVIRONMENT SETUP    PHP 
12 
 
 The PHP source distribution http://www.php.net/downloads.php 
The latest Apache source distribution  
http://httpd.apache.org/download.cgi


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http://httpd.apache.org/download.cgi 
 
 A working PHP -supported database, if you plan to use one ( For example MySQL, 
Oracle etc. ) 
 
 Any other supported software to which PHP must connect (mail server, BCMath 
package, JDK, and so forth) 
 
 An ANSI C compiler 
 
 Gnu make utility - you can freely download it at 
http://www.gnu.org/software/make 
 
Now here are the steps to install Apache and PHP5 on your Linux or Unix machine. If your


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PHP or Apache versions are different, then please take care accordingly. 
  
 If you haven't already done so, unzip and untar your Apache source distribution. Unless 
you have a reason to do otherwise, /usr/local is the standard place. 
gunzip -c apache_1.3.x.tar.gz 
tar -xvf apache_1.3.x.tar 
 Build the apache Server as follows 
cd apache_1.3.x 
./configure --prefix=/usr/local/apache --enable-so 
make 
make install


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make 
make install 
 Unzip and untar your PHP source distribution. Unless you have a reason to do 
otherwise, /usr/local is the standard place. 
gunzip -c php-5.x.tar.gz 
tar -xvf php-5.x.tar 
cd php-5.x 
 Configure and Build your PHP, assuming you are using MySQL database. 
./configure --with-apxs=/usr/sbin/apxs \ 
            --with-mysql=/usr/bin/mysql 
make 
make install 
 Install the php.ini file. Edit this file to get configuration directives: 
cd ../../php-5.x


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cd ../../php-5.x 
cp php.ini-dist /usr/local/lib/php.ini 
    PHP 
13 
 
 Tell your Apache server where you want to serve files from, and what extension(s) 
you want to identify PHP files. .php is the standard, but you can use .html, .phtml, or 
whatever you want. 
 
o Go to your HTTP configuration files (/usr/local/apache/conf or whatever your 
path is) 
 
o Open httpd.conf with a text editor. 
 
o Search for the word DocumentRoot (which should appear twice), and change


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both paths to the directory you want to serve files out of (in ou r case, 
/home/httpd). We recommend a home directory rather than the default 
/usr/local/apache/htdocs because it is more secure, but it doesn.t have to be 
in a home directory. You will keep all your PHP files in this directory. 
 
 Add at least one PHP extension directive, as shown in the first line of code that follows. 
In the second line, we.ve also added a second handler to have all HTML files parsed 
as PHP


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as PHP 
AddType application/x-httpd-php .php 
AddType application/x-httpd-php .html 
 Restart your server. Every time you change your HTTP configuration or php.ini files, 
you must stop and start your server again. 
cd ../bin 
./apachectl start 
 Set the document root directory permissions to world-executable. The actual PHP files 
in the directory need only be world-readable (644). If necessary, replace /home/httpd 
with your document root below: 
chmod 755 /home/httpd/html/php


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chmod 755 /home/httpd/html/php 
 Open a text editor. Type: <?php phpinfo(); ?>. Save this file in your Web server's 
document root as info.php. 
 
 Start any Web browser and browse the file. You must always use an HTTP request 
(http://www.testdomain.com/info.php or http://localhost/info.php or 
http://127.0.0.1/info.php) rather than a filename (/home/httpd/info.php) for the file 
to be parsed correctly 
 
You should see a long table of infor mation about your new PHP installation message


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Congratulations!    PHP 
14 
 
PHP Installation on Mac OS X with Apache 
Mac users have the choice of either a binary or a source installation. In fact, your OS X  
probably came with Apache and PHP preinstalled. This is likely to be quite an old build, and it 
probably lacks many of the less common extensions. 
 
However, if all you want is a quick Apache + PHP + MySQL/PostgreSQL setup on your laptop,


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this is certainly the easiest way to fly. All you need to do is edit your Apache configuration file 
and turn on the Web server. 
 
So just follow the steps given below: 
 
 Open the Apache config file in a text editor as root. 
sudo open -a TextEdit /etc/httpd/httpd.conf 
 
 Edit the file. Uncomment the following lines: 
Load Module php5_module 
AddModule mod_php5.c 
AddType application/x-httpd-php .php 
 You may also want to uncomment the <Directory /home/*/Sites> block or otherwise


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tell Apache which directory to serve out of. 
 
 Restart the Web server 
sudo apachectl graceful 
 Open a text editor. Type: <?php phpinfo(); ?>. Save this file in your Web server's 
document root as info.php. 
  
 Start any Web browser and browse the file.you must always use an HTTP request  
(http://www.testdomain.com/info.php or http://localhost/info.php or 
http://127.0.0.1/info.php) rather than a filename (/home/httpd/info.php) for the file 
to be parsed correctly


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to be parsed correctly 
 
You should see a long table of information about your new PHP installation message 
Congratulations! 
PHP Installation on Windows NT/2000/XP with IIS 
The Windows server installation of PHP running IIS is much simpler than on Unix, since it 
involves a precompiled binary rather than a source build. 
 
If you plan to install PHP over Windows, then here is the list of prerequisites:  
    PHP 
15


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PHP 
15 
 
 A working PHP-supported Web server. Under previous versions of PHP, IIS/PWS was 
the easiest choice because a module version of PHP was ava ilable for it; but PHP now 
has added a much wider selection of modules for Windows. 
 
 A correctly installed PHP-supported database like MySQL or Oracle etc. (if you plan to 
use one) 
 
 The PHP Windows binary distribution (download it atwww.php.net/downloads.php)


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 A utility to unzip files (search http://download.cnet.com for PC file compression 
utilities) 
 
Now here are the steps to install Apache and PHP5 on your Windows machine. If your PHP 
version is different, then please take care accordingly. 
  
 Extract the binary archive using your unzip utility; C:\PHP is a common location. 
 
 Copy some .dll files from your PHP directory to your systems directory (usually


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C:\Winnt\System32). You need php5ts.dll for every case. You will also probably need 
to copy the file corresponding to your Web server module - C:\PHP\Sapi\php5isapi.dll. 
It's possible you will also need others from the dlls subfolder - but start with the two 
mentioned above and add more if you need them. 
 
 Copy either php.ini -dist or php.ini -recommended (preferably the latter) to your 
Windows directory (C:\Winnt or C:\Winnt40), and rename it php.ini. Open this file in


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a text editor (for example, Notepad). Edit this file to get configuration directives; We 
highly recommend new users set error reporting to E_ALL on their development 
machines at this point. For now, the most important thing is the doc_root directive 
under the Paths and Directories section.  make sure this matches yo ur IIS Inetpub 
folder (or wherever you plan to serve out of). 
 
 Stop and restart the WWW service. Go to the Start menu -> Settings -> Control Panel


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-> Services. Scroll down the list to IIS Admin Service. Select it and click Stop. After it 
stops, select Worl d Wide Web Publishing Service and click Start. Stopping and 
restarting the service from within Internet Service Manager will not suffice. Since this 
is Windows, you may also wish to reboot. 
 
 Open a text editor. Type: <?php phpinfo(); ?>. Save this file in your Web server's 
document root as info.php.


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document root as info.php. 
 
 Start any Web browser and browse the file.you must always use an HTTP request 
(http://www.testdomain.com/info.php or http://localhost/info.php or 
http://127.0.0.1/info.php) rather than a filename (/home/httpd/i nfo.php) for the file 
to be parsed correctly 
 
You should see a long table of information about your new PHP installation message 
Congratulations!    PHP 
16 
 
PHP Installation on Windows NT/2000/XP with Apache


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To install Apache with PHP 5 on Windows follow the following steps. If your PHP and Apache 
versions are different, then please take care accordingly. 
 
 Download Apache server from www.apache.org/dist/httpd/binaries/win32. You want 
the current  stable release version with the no_src.msi extension. Double -click the 
installer file to install; C: \Program Files is a common location. The installer will also 
ask you whether you want to run Apache as a service or from the command line or


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DOS prompt. We  recommend you do not install as a service, as this may cause 
problems with startup. 
 
 Extract the PHP binary archive using your unzip utility; C:\PHP is a common location. 
 
 Copy some .dll files from your PHP directory to your system directory (usually 
C:\Windows). You need php5ts.dll for every case. You will also probably need to copy 
the file corresponding to your Web server module - C:\PHP\Sapi\php5apache.dll. to


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your Apache modules directory. It's possible that you will also need others from the 
dlls subfolder, but start with the two mentioned previously and add more if you need 
them. 
 
 Copy either php.ini -dist or php.ini -recommended (preferably the latter) to your 
Windows directory, and rename it php.ini. Open this file in a text editor (for example, 
Notepad). Edit this file to get configuration directives; At this point, we highly


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recommend that new users set error reporting to E_ALL on their development 
machines. 
 
 Tell your Apache server where you want to serve files from and what extension(s) you 
want to identify PHP files (.php is the standard, but you can use .html, .phtml, or 
whatever you want). Go to your HTTP configuration files (C: \Program Files \Apache 
Group\Apache\conf or whatever your path is), and open httpd.conf with a text editor.


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Search for the word DocumentRoot (which should appear twice) and change both paths 
to the directory you want to serve files out of. (The default is C:\Program Files\Apache 
Group\Apache\htdocs.). Add at least one PHP extension directive as shown in the first 
line of the following code: 
 
LoadModule php5_module modules/php5apache.dll 
AddType application/x-httpd-php .php .phtml 
  
 You may also need to add the following line: 
AddModule mod_php5.c


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AddModule mod_php5.c 
 Stop and restart the WWW service. Go to the Start menu -> Settings -> Control Panel 
-> Services. Scroll down the list to IIS Admin Service. Select it and click Stop. After it 
stops, select World Wide Web Publishing Service and click Start. Stopping and 
restarting the service from within Internet Service Manager will not suffice. Sin ce this 
is Windows, you may also wish to reboot.    PHP 
17


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17 
 
 
 Open a text editor. Type: <?php phpinfo(); ?>. Save this file in your Web server's 
document root as info.php. 
 
 Start any Web browser and browse the file.you must always use an HTTP request 
(http://www.testdomain.com/info.php or http://localhost/info.php or 
http://127.0.0.1/info.php) rather than a filename (/home/httpd/info.php) for the file 
to be parsed correctly 
 
You should see a long table of information about your new PHP installation message 
Congratulations!


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Congratulations! 
 
Apache Configuration 
If you are using Apache as a Web Server , then this section will guide you to edit Apache 
Configuration Files. 
 
PHP.INI File Configuration 
The PHP configuration file, php.ini, is the final and most immediate way to affect PHP's 
functionality. 
 
Just Check it here: PHP.INI File Configuration 
 
Windows IIS Configuration 
To configure IIS on your Windows machine you can refer your IIS Reference Manual shipped 
along with IIS.


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along with IIS. 
 
Apache Configuration for PHP 
Apache uses httpd.conf file for global settings, and the .htaccess  file for per-directory access 
settings. Older versions of Apache split up httpd.conf into three files (access.conf, httpd.conf, 
and srm.conf), and some users still prefer this arrangement. 
 
Apache server has a very powerful, but slightly complex, configur ation system of its own. 
Learn more about it at the Apache Web site: www.apache.org


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The following section describe s settings in httpd.conf that affect PHP directly and cannot be 
set elsewhere. If you have standard installation , then httpd.conf will be found at 
/etc/httpd/conf: 
Timeout 
This value sets the default number of seconds before any HTTP request will time out. If you 
set PHP's max_execution_time to longer than this value, PHP will keep grinding away but the    PHP 
18


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18 
 
user may see a 404 error. In safe mode, this value will be ignored; you must use the timeout 
value in php.ini instead 
DocumentRoot 
DocumentRoot designates the root directory for all HTTP processes on that server. It looks 
something like this on Unix: 
DocumentRoot ./usr/local/apache_1.3.6/htdocs. 
You can choose any directory as document root. 
 
AddType 
The PHP MIME type needs to be set here for PHP files to be  parsed. Remember that you can


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associate any file extension with PHP like .php3, .php5 or .htm. 
AddType application/x-httpd-php .php 
AddType application/x-httpd-phps .phps 
AddType application/x-httpd-php3 .php3 .phtml 
AddType application/x-httpd-php .html 
Action 
You must uncomment this line for the Windows apxs module version of Apache with shared 
object support: 
LoadModule php4_module modules/php4apache.dll 
or on Unix flavors: 
LoadModule php4_module modules/mod_php.so 
 
AddModule


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AddModule 
You must uncomment this line for the static module version of Apache. 
AddModule mod_php4.c 
PHP .INI file Configuration 
The PHP configuration file, php.ini, is the final and most immediate way to affect PHP's 
functionality. The php.ini file is read each time PHP is initialized.in other words, whenever 
httpd is restarted for the module version or with each script execution for the CGI version. If    PHP 
19


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19 
 
your change isn’t showing up, remember to stop and restart httpd. If it still isn’t showing up, 
use phpinfo() to check the path to php.ini. 
 
The configuration file is well commented and thorough. Keys are case sensitive, keyword 
values are not; whitespace, and lines beginning with semicolons are ignored. Booleans can 
be represented by 1/0, Yes/No, On/Off, or True/False. The default v alues in php.ini-dist will 
result in a reasonable PHP installation that can be tweaked later.


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Here we are explaining the important settings in php.ini which you may need for your PHP 
Parser. 
short_open_tag = Off 
Short open tags look like this: <? ?>. This option must be set to Off if you want to use XML 
functions. 
safe_mode = Off 
If this is set to On, you probably compiled PHP with the --enable-safe-mode flag. Safe mode 
is most relevant to CGI use. See the explanation in the section "CGI compile -time options". 
earlier in this chapter. 
safe_mode_exec_dir = [DIR]


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safe_mode_exec_dir = [DIR] 
This option is relevant only if safe mode is on; it can also be set with the --with-exec-dir flag 
during the Unix build process. PHP in safe mode only executes external binaries out of this 
directory. The default is /usr/local/bin. This has nothing to do with serving up a normal 
PHP/HTML Web page. 
 
safe_mode_allowed_env_vars = [PHP_] 
This option sets which environment variables users can change in safe mode. The default is


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only those variables prepended with "PHP_". If this directive is empty, most variables are 
alterable. 
safe_mode_protected_env_vars = [LD_LIBRARY_PATH] 
This option sets which environment variables users can't change in safe mode, even if 
safe_mode_allowed_env_vars is set permissively. 
 
disable_functions = [function1, function2...] 
A welcome addition to PHP4 configuration and one perpetuated in PHP5 is the ability to disable


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selected functions for security reasons. Previously, this necessitated hand -editing the C code 
from which PHP was made. Filesystem, system, and network functions should probably be the 
first to go because allowing the capability to write files and alter the system over HTTP is 
never such a safe idea.    PHP 
20 
 
max_execution_time = 30 
The function set_time_limit() won.t  work in safe mode, so this is the main way to make a


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script time out in safe mode. In Windows, you have to abort based on maximum memory 
consumed rather than time. You can also use the Apache timeout setting to timeout if you 
use Apache, but that will apply to non-PHP files on the site too. 
error_reporting = E_ALL & ~E_NOTICE 
The default value is E_ALL & ~E_NOTICE, all errors except notices. Development servers 
should be set to at least the default; only production servers should even consider a lesser 
value 
error_prepend_string = [""]


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value 
error_prepend_string = [""] 
With its bookend, error_append_string, this setting allows you to make error messages a 
different color than other text, or what  you have. 
warn_plus_overloading = Off 
This setting issues a warning if the + operator is used with strings, as in a form value. 
variables_order = EGPCS 
This configuration setting supersedes gpc_order. Both are now deprecated along with 
register_globals. It sets the order of the different variables: Environment, GET, POST,


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COOKIE, and SERVER (aka Built-in). 
 
You can change this order around. Variables will be overwritten successively in left -to-right 
order, with the rightmost one winning the hand every time. This means if you left the default 
setting and happened to use the same name for an en vironment variable, a POST variable, 
and a COOKIE variable, the COOKIE variable would own that name at the end of the process. 
In real life, this doesn't happen much. 
 
register_globals = Off


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register_globals = Off 
This setting allows you to decide whether you wish to register EGPCS variables as global. This 
is now deprecated, and as of PHP4.2, this flag is set to Off by default. Use superglobal arrays 
instead. All the major code listings in this book use superglobal arrays. 
gpc_order = GPC 
This setting has been GPC Deprecated. 
 
 
 
    PHP 
21 
 
magic_quotes_gpc = On 
This setting escapes quotes in incoming GET/POST/COOKIE data. If you use a lot of forms


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string_value:
which possibly submit to themselves or other forms and display form values, you may need 
to set this directive to On or prepare to use addslashes() on string-type data. 
magic_quotes_runtime = Off 
This setting escapes quotes in incoming database and text strings. Remember that SQL adds 
slashes to single quotes and apostrophes when storing strings and does not strip them off 
when returning them. If this setting is Off, you will need to use stripslashes() when outputting


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string_value:
any type of string data from a SQL database. If magic_quotes_sybase is set to On, this must 
be Off. 
magic_quotes_sybase = Off 
This setting escapes single quotes in incoming database and text strings with Sybase -style 
single quotes rather than backslashes. If magic_quotes_runtime is set to On, this must be 
Off. 
auto-prepend-file = [path/to/file] 
If a path is specified here, PHP must automatically include() it at the beginning of every PHP 
file. Include path restrictions do apply.


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string_value:
file. Include path restrictions do apply. 
auto-append-file = [path/to/file] 
If a path is specified here, PHP must automatically include() it at the end of every PHP 
file.unless you escape by using the exit() function. Include path restrictions do apply . 
include_path = [DIR] 
If you set this value, you will only be allowed to include or require files from these directories. 
The include directory is generally under your document root; this is mandatory if you.re


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string_value:
running in safe mode. Set this to . in order to include files from the same directory your script 
is in. Multiple directories are separated by colons: .:/usr/local/apache/htdocs:/usr/local/lib.  
doc_root = [DIR] 
If you.re using Apache, you.ve already set a document root for this server or virtual hos t in 
httpd.conf. Set this value here if you.re using safe mode or if you want to enable PHP only on 
a portion of your site (for example, only in one subdirectory of your Web root).


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string_value:
file_uploads = [on/off] 
Turn on this flag if you will upload files using PHP script. 
upload_tmp_dir = [DIR] 
Do not uncomment this line unless you understand the implications of HTTP uploads!     PHP 
22 
 
session.save-handler = files 
Except in rare circumstances, you will not want to change this setting. So don't touch it.  
ignore_user_abort = [On/Off] 
This setting controls what happens if a site visitor clicks the browser.s Stop button. The default


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string_value:
is On, which means that the script continues to run to completion or timeout. If the setting is 
changed to Off, the script will abort. This setting only works in module mode, not CGI. 
mysql.default_host = hostname 
The default server host to use when connecting to the database server if no other host is 
specified. 
mysql.default_user = username 
The default user name to use when connecting to the datab ase server if no other name is 
specified. 
mysql.default_password = password


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string_value:
specified. 
mysql.default_password = password 
The default password to use when connecting to the database server if no other password is 
specified. 
    PHP 
23 
 
Escaping to PHP 
The PHP parsing engine needs a way to differentiate PHP code from other elements in the 
page. The mechanism for doing so is known as 'escaping to PHP.' There are four ways to do  
this: 
Canonical PHP tags 
The most universally effective PHP tag style is: 
<?php...?>


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string_value:
<?php...?> 
If you use this style, you can be positive that your tags will always be correctly interpreted.  
Short-open (SGML-style) tags 
Short or short-open tags look like this: 
<?...?> 
Short tags are, as one might expect, the shortest option You must do one of two things to 
enable PHP to recognize the tags: 
 
 Choose the --enable-short-tags configuration option when you're building PHP. 
 
 Set the short_open_tag setting in your php.ini file to on. This option must be disabled


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string_value:
to parse XML with PHP because the same syntax is used for XML tags. 
ASP-style tags 
ASP-style tags mimic the tags used by Active Server Pages to delineate code blocks. ASP -
style tags look like this: 
<%...%> 
To use ASP-style tags, you will need to set the configuration option in your php.ini file.  
HTML script tags 
HTML script tags look like this: 
<script language="PHP">...</script> 
 PHP ─ SYNTAX OVERVIEW    PHP 
24 
 
 
Commenting PHP Code


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string_value:
24 
 
 
Commenting PHP Code 
A comment is the portion of a program that exists only for the human reader and stripped out 
before displaying the programs result. There are two commenting formats in PHP:  
 
Single-line comments: They are generally used for short explanations or notes relevant to 
the local code. Here are the examples of single line comments. 
<? 
# This is a comment, and 
# This is the second line of the comment 
// This is a comment too. Each style comments only


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string_value:
print "An example with single line comments"; 
?> 
 
Multi-lines printing:  Here are the examples to print multiple lines in a single print 
statement: 
<? 
# First Example 
print <<<END 
This uses the "here document" syntax to output 
multiple lines with $variable interpolation. Note 
that the here document terminator must appear on a 
line with just a semicolon no extra whitespace! 
END; 
# Second Example 
print "This spans 
multiple lines. The newlines will be 
output as well"; 
?>


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string_value:
output as well"; 
?> 
 
Multi-lines comments: They are generally used to provide pseudocode algorithms and more 
detailed explanations when necessary. The multiline style of commenting is the same as in C. 
Here are the example of multi lines comments. 
<? 
/* This is a comment with multiline 
    Author : Mohammad Mohtashim 
    Purpose: Multiline Comments Demo 
    Subject: PHP 
*/ 
print "An example with multi line comments"; 
?>    PHP 
25 
 
PHP is whitespace insensitive


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string_value:
?>    PHP 
25 
 
PHP is whitespace insensitive 
Whitespace is the stuff you type that is typically invisible on the screen, including spaces, 
tabs, and carriage returns (end-of-line characters). 
 
PHP whitespace insensitive means that it almost never matters how many whitespace 
characters you have in a row.one whitespace character is the same as many such characters. 
 
For example, each of the following PHP statements that assigns the sum of 2 + 2 to the 
variable $four is equivalent:


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string_value:
variable $four is equivalent: 
$four = 2 + 2; // single spaces 
$four <tab>=<tab2<tab>+<tab>2 ; // spaces and tabs 
$four = 
2+ 
2; // multiple lines 
PHP is case sensitive 
Yeah it is true that PHP is a case sensitive language. Try out the following example: 
<html> 
<body> 
<? 
$capital = 67; 
print("Variable capital is $capital<br>"); 
print("Variable CaPiTaL is $CaPiTaL<br>"); 
?> 
</body> 
</html> 
This will produce the following result: 
Variable capital is 67 
Variable CaPiTaL is


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string_value:
Variable capital is 67 
Variable CaPiTaL is 
Statements are expressions terminated by semicolons 
A statement in PHP is any expression that is followed by a semicolon (;).Any sequence of valid 
PHP statements that is enclosed by the PHP tags is a valid PHP program. Here is a typical 
statement in PHP, which in this case assigns a string of characters to a variable called 
$greeting: 
 
$greeting = "Welcome to PHP!";    PHP 
26 
 
Expressions are combinations of tokens


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string_value:
26 
 
Expressions are combinations of tokens 
The smallest building blocks of PHP are the indivisible tokens, such as numbers (3.14159), 
strings (.two.), variables ($two), constants (TRUE), and the special words that make up the 
syntax of PHP itself like if, else, while, for and so forth 
Braces make blocks 
Although statements cannot be combined like expressions, you can always put a sequence of 
statements anywhere a statement can go by enclosing them in a set of curly braces.


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string_value:
Here both statements are equivalent: 
 
 
if (3 == 2 + 1) 
  print("Good - I haven't totally lost my mind.<br>"); 
 
if (3 == 2 + 1) 
{ 
   print("Good - I haven't totally"); 
   print("lost my mind.<br>"); 
} 
Running PHP Script from Command Prompt 
Yes you can run your PHP script on your command prompt. Assuming you have the following 
content in test.php file 
<?php 
   echo "Hello PHP!!!!!"; 
?> 
Now run this script as command prompt as follows: 
$ php test.php


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string_value:
$ php test.php 
It will produce the following result 
Hello PHP!!!!! 
 
 
    PHP 
27 
 
The main way to store information in the middle of a PHP program is by using a variable.  
Here are the most important things to know about variables in PHP. 
 
 All variables in PHP are denoted with a leading dollar sign ($). 
 
 The value of a variable is the value of its most recent assignment. 
 
 Variables are assigned with the = operator, with the variable on the left-hand side and


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string_value:
the expression to be evaluated on the right. 
 
 Variables can, but do not need, to be declared before assignment. 
 
 Variables in PHP do not have intrinsic types - a variable does not know in advance 
whether it will be used to store a number or a string of characters. 
 
 Variables used before they are assigned have default values. 
 
 PHP does a good job of automatically converti ng types from one to another when 
necessary. 
 
 PHP variables are Perl-like.


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string_value:
necessary. 
 
 PHP variables are Perl-like. 
 
PHP has a total of eight data types which we use to construct our variables: 
 
 Integers: are whole numbers, without a decimal point, like 4195. 
 
 Doubles: are floating-point numbers, like 3.14159 or 49.1. 
 
 Booleans: have only two possible values either true or false. 
 
 NULL: is a special type that only has one value: NULL. 
 
 Strings: are sequences of characters, like 'PHP supports string operations.'


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string_value:
 Arrays: are named and indexed collections of other values. 
 
 Objects: are instances of programmer -defined classes, which can package up both 
other kinds of values and functions that are specific to the class. 
 
 Resources: are special variables that hold references to resources external t o PHP 
(such as database connections). 
 
The first five are  simple types, and the next two (arrays and objects) are compound - the


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string_value:
compound types can package up other arbitrary values of arbitrary type, whereas the simple 
types cannot. 
 PHP ─ VARIABLE TYPES    PHP 
28 
 
 
We will explain only simile data type in this chapters. Array and Objects will be explained 
separately. 
Integers 
They are whole numbers, without a decimal point, like 4195. They are the simplest type .they 
correspond to simple whole numbers, both positive and negative. Integer s can be assigned


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string_value:
to variables, or they can be used in expressions, like so: 
$int_var = 12345; 
$another_int = -12345 + 12345; 
Integer can be in decimal (base 10), octal (base 8), and hexadecimal (base 16) format. 
Decimal format is the default, octal integers are specified with a leading 0, and hexadecimals 
have a leading 0x. 
 
For most common platforms, the largest integer is (2**31 . 1) (or 2,147,483,647), and the 
smallest (most negative) integer is . (2**31 . 1) (or .2,147,483,647). 
Doubles


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string_value:
Doubles 
They like 3.14159 or 49.1. By default, doubles print with the minimum number of decimal 
places needed. For example, the code: 
$many = 2.2888800; 
$many_2 = 2.2111200; 
$few = $many + $many_2; 
print(.$many + $many_2 = $few<br>.); 
It produces the following browser output: 
2.28888 + 2.21112 = 4.5 
Boolean 
They have only two possible values either true or false. PHP provides a couple of constants 
especially for use as Booleans: TRUE and FALSE, which can be used like so: 
if (TRUE)


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string_value:
if (TRUE) 
   print("This will always print<br>"); 
else 
   print("This will never print<br>");    PHP 
29 
 
Interpreting other types as Booleans 
Here are the rules for determine the "truth" of any value not already of the Boolean type:  
 
 If the value is a number, it is false if exactly equal to zero and true otherwise.  
 
 If the value is a string, it is false if the string is empty (has zero characters) or is the 
string "0", and is true otherwise.


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string_value:
string "0", and is true otherwise. 
 
 Values of type NULL are always false. 
 
 If the value is an array, it is false if it contains no other values, and it is true otherwise. 
For an object, containing a value means having a member variable that has been 
assigned a value. 
 
 Valid resources are true (although some functions that return resources when they are 
successful will return FALSE when unsuccessful). 
 
 Don't use double as Booleans.


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string_value:
 Don't use double as Booleans. 
 
Each of the following variables has the truth value embedded in its name when it is used in a 
Boolean context. 
$true_num = 3 + 0.14159; 
$true_str = "Tried and true" 
$true_array[49] = "An array element"; 
$false_array = array(); 
$false_null = NULL; 
$false_num = 999 - 999; 
$false_str = ""; 
NULL 
NULL is a special type that only has one value: NULL. To give a variable the NULL value, 
simply assign it like this: 
$my_var = NULL;


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string_value:
simply assign it like this: 
$my_var = NULL; 
The special constant NULL is capitalized by convention, but actually it is case insensitive; you 
could just as well have typed: 
$my_var = null; 
A variable that has been assigned NULL has the following properties: 
 
 It evaluates to FALSE in a Boolean context. 
     PHP 
30 
 
 It returns FALSE when tested with IsSet() function. 
Strings 
They are sequences of characters, like "PHP supports string operations". Following are valid


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string_value:
examples of string: 
$string_1 = "This is a string in double quotes"; 
$string_2 = "This is a somewhat longer, singly quoted string"; 
$string_39 = "This string has thirty-nine characters"; 
$string_0 = ""; // a string with zero characters 
Singly quoted strings are treated almost literally, whereas doubly quoted strings replace 
variables with their values as well as specially interpreting certain character sequences.  
<? 
$variable = "name"; 
$literally = 'My $variable will not print!\\n';


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string_value:
$literally = 'My $variable will not print!\\n'; 
print($literally); 
$literally = "My $variable will print!\\n"; 
print($literally); 
?> 
 
This will produce the following result: 
My $variable will not print!\n 
My name will print 
There are no artificial limits on string length - within the bounds of available memory, you 
ought to be able to make arbitrarily long strings. 
 
Strings that are delimited by double quotes (as in "this") are preprocessed in both the 
following two ways by PHP:


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string_value:
following two ways by PHP: 
 
 Certain character sequences beginning with backslash ( \) are replaced with special 
characters 
 
 Variable names (starting with $) are replaced with string representations of their 
values. 
 
The escape-sequence replacements are: 
 
 \n is replaced by the newline character 
    PHP 
31 
 
 \r is replaced by the carriage-return character 
 
 \t is replaced by the tab character 
 
 \$ is replaced by the dollar sign itself ($)


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string_value:
 \$ is replaced by the dollar sign itself ($) 
 
 \" is replaced by a single double-quote (") 
 
 \\ is replaced by a single backslash (\) 
 
Here Document 
You can assign multiple lines to a single string variable using here document: 
<?php 
 
$channel =<<<_XML_ 
<channel> 
<title>What's For Dinner<title> 
<link>http://menu.example.com/<link> 
<description>Choose what to eat tonight.</description> 
</channel> 
_XML_; 
 
echo <<<END 
This uses the "here document" syntax to output


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string_value:
This uses the "here document" syntax to output 
multiple lines with variable interpolation. Note 
that the here document terminator must appear on a 
line with just a semicolon. no extra whitespace! 
<br /> 
END; 
 
print $channel; 
?> 
This will produce the following result: 
This uses the "here document" syntax to output 
 
multiple lines with variable interpolation. Note    PHP 
32 
 
that the here document terminator must appear on a 
line with just a semicolon. no extra whitespace!


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string_value:
<channel> 
<title>What's For Dinner<title> 
<link>http://menu.example.com/<link> 
<description>Choose what to eat tonight.</description> 
 
 
 
Variable Naming 
Rules for naming a variable is: 
 
 Variable names must begin with a letter or underscore character. 
 
 A variable name can consist of numbers, letters, underscor es but you cannot use 
characters like + , - , % , ( , ) . & , etc 
 
There is no size limit for variables. 
PHP – V ariables


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string_value:
PHP – V ariables 
Scope can be defined as the range of availability a variable has to the program in which it is 
declared. PHP variables can be one of four scope types: 
 
 Local variables 
 
 Function parameters 
 
 Global variables 
 
 Static variables 
PHP Local Variables 
A variable declared in a function is considered local; that is, it can be referenced solely in that 
function. Any assignment outside of that function will be considered to be an entirely different


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string_value:
variable from the one contained in the function: 
<? 
$x = 4; 
function assignx () {    PHP 
33 
 
$x = 0; 
print "\$x inside function is $x.  
"; 
} 
assignx(); 
print "\$x outside of function is $x.  
"; 
?> 
This will produce the following result. 
$x inside function is 0. 
$x outside of function is 4. 
PHP Function Parameters 
PHP Functions are covered in detail in  PHP Function Chapter. In short, a function is a small


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string_value:
unit of program which can take some input in the form of parameters and does some 
processing and may return a value. 
 
Function parameters are declared after the function name and inside parentheses. They are 
declared much like a typical variable would be: 
<? 
// multiply a value by 10 and return it to the caller 
function multiply ($value) { 
    $value = $value * 10; 
    return $value; 
} 
 
$retval = multiply (10); 
Print "Return value is $retval\n"; 
?>


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string_value:
Print "Return value is $retval\n"; 
?> 
This will produce the following result. 
Return value is 100    PHP 
34 
 
PHP Global Variables 
In contrast to local variables, a global variable can be accessed in any part of the program. 
However, in order to be modified, a global variable must be explicitly declared to be global in 
the func tion in which it is to be modified. This is accomplished, conveniently enough, by


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string_value:
placing the keyword  GLOBAL in front of the variable that should be recognized as global. 
Placing this keyword in front of an already existing variable tells PHP to use the variable having 
that name. Consider an example: 
<? 
$somevar = 15; 
function addit() { 
GLOBAL $somevar; 
$somevar++; 
print "Somevar is $somevar"; 
} 
addit(); 
?> 
 
 
 
This will produce the following result. 
Somevar is 16 
PHP Static V ariables


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string_value:
Somevar is 16 
PHP Static V ariables 
The final type of variable scoping that I discuss is known as static. In contrast to the variables 
declared as function parameters, which are destroyed on the function's exit, a static variable 
will not lose its value when the function exits and will still hold that value should the function 
be called again. 
 
You can declare a variable to be static simply by placing the keyword STATIC in front of the 
variable name. 
<? 
function keep_track() {


key: chroma:document
string_value:
variable name. 
<? 
function keep_track() { 
   STATIC $count = 0; 
   $count++; 
   print $count; 
   print " 
";    PHP 
35 
 
} 
keep_track(); 
keep_track(); 
keep_track(); 
?> 
This will produce the following result. 
1 
2 
3 
    PHP 
36 
 
A constant is a name or an identifier for a simple value. A constant value cannot change 
during the execution of the script. By default , a constant is case -sensitive. By convention,


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string_value:
constant identifiers are always uppercase. A constant name starts with a letter or underscore, 
followed by any number of letters, numbers, or underscores. If you have defined a constant, 
it can never be changed or undefined. 
 
To define a constant you have to use define() function and to retrieve the value of a constant, 
you have to simply specifying its name. Unlike with variables, you do not need to have a


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string_value:
constant with a $. You can also use the function constant() to read a constant's va lue if you 
wish to obtain the constant's name dynamically. 
constant() function 
As indicated by the name, this function will return the value of the constant. 
 
This is useful when you want to retrieve value of a constant, but you do not know its name, 
i.e., it is stored in a variable or returned by a function. 
constant() example 
<?php 
 
define("MINSIZE", 50); 
 
echo MINSIZE;


key: chroma:document
string_value:
<?php 
 
define("MINSIZE", 50); 
 
echo MINSIZE; 
echo constant("MINSIZE"); // same thing as the previous line 
 
?> 
Only scalar data (boolean, integer, float and string) can be contained in constants. 
Differences between constants and variables are 
 There is no need to write a dollar sign ($) before a constant, where as in Variable one 
has to write a dollar sign. 
 
 Constants cannot be defined by simple assignment, they may only be defined using 
the define() function.


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string_value:
the define() function. 
 
 Constants may be defined and accessed anywhere without regard to variable scoping 
rules. 
 PHP ─ CONSTANTS    PHP 
37 
 
 
 Once the Constants have been set, may not be redefined or undefined. 
 
Valid and invalid constant names 
// Valid constant names 
define("ONE",     "first thing"); 
define("TWO2",    "second thing"); 
define("THREE_3", "third thing") 
// Invalid constant names 
define("2TWO",    "second thing"); 
define("__THREE__", "third value");


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string_value:
define("__THREE__", "third value");  
PHP Magic constants 
PHP provides a large number of predefined constants to any script which it runs. 
 
There are five magical constants that change depending on where they are used. For example, 
the value of __LINE__ depends on the line that it's used on in your script. These special 
constants are case-insensitive and are as follows: 
 
The following table lists a few "magical" PHP constants along with their description:  
 
Name Description


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string_value:
Name Description 
__LINE__ The current line number of the file. 
__FILE__ The full path and filename of the file. If used inside an include, the 
name of the included file is returned. Since PHP 
4.0.2, __FILE__ always contains an absolute path whereas in older 
versions it contained relative path under some circumstances. 
__FUNCTION__ The function name. (Added in PHP 4.3.0) As  of PHP 5 this constant 
returns the function name as it was declared (case-sensitive). In PHP


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string_value:
4 its value is always lowercased. 
__CLASS__ The class name. (Added in PHP 4.3.0) As of PHP 5 this constant 
returns the class name as it was declared (case-sensitive). In PHP 4 
its value is always lowercased. 
__METHOD__ The class method name. (Added in PHP 5.0.0) The method name is 
returned as it was declared (case-sensitive).    PHP 
38 
 
What is Operator? Simple answer can be given using expression  4 + 5 is equal to 9. Here


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string_value:
4 and 5 are called operands and + is called operator. PHP language supports following type 
of operators. 
 
 Arithmetic Operators 
 
 Comparison Operators 
 
 Logical (or Relational) Operators 
 
 Assignment Operators 
 
 Conditional (or ternary) Operators 
 
Let’s have a look on all operators one by one. 
Arithmetic Operators  
The following arithmetic operators are supported by PHP language: 
 
Assume variable A holds 10 and variable B holds 20 then: 
 
Operator Description Example


key: chroma:document
string_value:
Operator Description Example 
+ Adds two operands A + B will give 30 
- Subtracts second operand from the first A - B will give -10 
* Multiply both operands A * B will give 200 
/ Divide the numerator by denominator B / A will give 2 
% Modulus Operator and remainder of after an 
integer division 
B % A will give 0 
++ Increment operator, increases integer value by 
one 
A++ will give 11 
-- Decrement operator, decreases integer value 
by one 
A-- will give 9 
 
 PHP ─ OPERATOR TYPES    PHP


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string_value:
A-- will give 9 
 
 PHP ─ OPERATOR TYPES    PHP 
39 
 
Example 
Try the following example to understand all the arithmetic operators. Copy and paste following 
PHP program in test.php file and  keep it in your PHP Server's document root and browse it 
using any browser. 
 
<html> 
<head><title>Arithmetical Operators</title><head> 
<body> 
<?php 
    $a = 42; 
    $b = 20; 
     
    $c = $a + $b; 
    echo "Addition Operation Result: $c <br/>"; 
    $c = $a - $b;


key: chroma:document
string_value:
$c = $a - $b; 
    echo "Subtraction Operation Result: $c <br/>"; 
    $c = $a * $b; 
    echo "Multiplication Operation Result: $c <br/>"; 
    $c = $a / $b; 
    echo "Division Operation Result: $c <br/>"; 
    $c = $a % $b; 
    echo "Modulus Operation Result: $c <br/>"; 
    $c = $a++;  
    echo "Increment Operation Result: $c <br/>"; 
    $c = $a--;  
    echo "Decrement Operation Result: $c <br/>"; 
?> 
</body> 
</html> 
This will produce the following result:


key: chroma:document
string_value:
</html> 
This will produce the following result: 
Addition Operation Result: 62 
Subtraction Operation Result: 22 
Multiplication Operation Result: 840 
Division Operation Result: 2.1    PHP 
40 
 
Modulus Operation Result: 2 
Increment Operation Result: 42 
Decrement Operation Result: 43 
     PHP 
41 
 
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