Home Backend Development PHP Tutorial Detailed interpretation of the application of interfaces in PHP_php skills

Detailed interpretation of the application of interfaces in PHP_php skills

May 16, 2016 pm 08:08 PM
php interface

Interface
PHP classes are single inheritance, that is, they do not support multiple inheritance. When a class requires the functions of multiple classes, inheritance is powerless. For this reason, PHP introduces interface technology

If all methods in an abstract class are abstract methods and no variables are declared, and all members in the interface have public permissions, then this special abstract class is called an interface

Interfaces are defined using the interface keyword, and implements are used to implement interface methods, which must be fully implemented

Implement an interface

The following is a practical example of PHP interface implementation. An interface named IPillage is created and implemented here. The IPillage interface is as follows:

1

2

3

4

5

interface IPillage

{

 function emptyBakAccount();

 function burnDocument();

}

Copy after login

Then implement this interface through the Executive class:

1

2

3

4

5

6

7

8

9

10

11

12

class Executive extends Employee implements IPillage

{

 private $totalStockOptions;

 function emptyBankAccount()

 {

  echo "Call CFO and ask to transfer funds to Swiss bank account.";

 }

 function burnDocuments()

 {

  echo "Torch the office suite.";

 }

}

Copy after login

Because people at all levels in the company can embezzle, there can be an Assistant class that implements this interface:

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

class Assistant extends Employee implements IPillage

{

 function takeMome()

 {

  echo "Taking memo...";

 }

 function emptyBankAccount()

 {

  echo "Go on shopping spree with office credit card.";

 }

 function burnDocuments()

 {

  echo "Start small fire in the trash can.";

 }

}

Copy after login

As you can see, the interface is particularly useful. Because, although they define how many methods are required to occur a certain behavior, as well as the names of each methods, interfaces allow different classes to implement these methods in different ways. In this example, for the method of burning files, the Assistdnt class just burns the files in the trash can, while the Executive class does it in a more extreme way (burning its office).

Implement multiple interfaces

It would be unfair if we allowed outside contractors to encroach on the company, after all the company was built with the efforts of all full-time employees. That is, how do you provide employees with jobs and encroach on company functions, while limiting contractors to only completing the required tasks? The solution is to break these tasks into several tasks and then implement the necessary multiple interfaces. PHPS supports this feature. Consider the following example:

1

2

3

4

5

6

7

8

9

10

11

<&#63;php

 interface IEmployee{...}

 interface IDeveloper{...}

 interface IPillage{...}

 class Employee implements IEmployee,IDeveloper,iPillage {

 ...

 }

 class Contractor implements IEmployee,IDeveloper {

 ...

 }

&#63;>

Copy after login


The difference between abstract classes and interfaces
An interface is a special abstract class, which can also be regarded as the specification of a model. The general differences between interfaces and abstract classes are as follows:

If a subclass implements an interface, it must implement all methods in the interface (whether needed or not); if it inherits an abstract class, it only needs to implement the required methods
If the method name defined in an interface changes, then all subclasses that implement this interface need to update the method name synchronously; and if the method name changes in an abstract class, the method name corresponding to its subclass will not be affected, but will become Just a new method
​​Abstract classes can only be inherited singly. When a subclass needs to implement functions that need to inherit from multiple parent classes, it must use interfaces


Code Example


1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

<&#63;php

  

/**

 * 声明接口Demo

 * @author wzy

 *

 */

interface Demo

{

  

 const NAME = "wangzhengyi";

  

 const AGE = 25;

  

 function fun1 (); // 声明方法默认是public abstract

 function fun2 ();

}

  

/**

 * 声明接口的继承Demo2

 *

 * @author wzy

 *  

 */

interface Demo2 extends Demo

{

  

 function fun3 ();

  

 function fun4 ();

}

  

/**

 * 声明接口Demo3

 *

 * @author wzy

 *  

 */

interface Demo3

{

  

 function fun5 ();

  

 function fun6 ();

}

  

/**

 * 声明父类ParentClass

 *

 * @author wzy

 *  

 */

class ParentClass

{

  

 function fun7 ();

}

  

/**

 * 子类必须实现接口中所有的方法

 *

 * @author wzy

 *  

 */

class ChildClass extends ParentClass implements Demo2, Demo3

{

  

 function fun1 ();

  

 function fun2 ();

  

 function fun3 ();

  

 function fun4 ();

  

 function fun5 ();

  

 function fun6 ();

}

Copy after login

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian Dec 24, 2024 pm 04:42 PM

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

How To Set Up Visual Studio Code (VS Code) for PHP Development How To Set Up Visual Studio Code (VS Code) for PHP Development Dec 20, 2024 am 11:31 AM

Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

PHP Program to Count Vowels in a String PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

How do you parse and process HTML/XML in PHP? How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

PHP and Python: Comparing Two Popular Programming Languages PHP and Python: Comparing Two Popular Programming Languages Apr 14, 2025 am 12:13 AM

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

See all articles