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Basic concepts of object-oriented php

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Jun 06, 2018 am 09:38 AM

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This article mainly introduces the basic concepts of PHP object-oriented, which has certain reference value. Now I share it with everyone. Friends in need can refer to it

Object

Object

Definition:

An object is a data structure in a program that is used to represent something.

Components:

contains variables and functions.

对象中的：

    变量 ——>  属性

    函数 ——>  方法

Class && Object

对象 --->  （归纳、总结）抽象    --->   类

类   --->  （具体化实现）实例化  --->   对象

Object-facing

Several major features: encapsulation, inheritance, polymorphism.

Encapsulation

Combine the properties and services of the object into an independent and identical unit, and hide the internal details of the object as much as possible, retaining only a limited external interface so that it can communicate with the outside. .

Inheritance

refers to the relationship between classes, and subclasses inherit from parent classes.

Polymorphism

Different forms.

Object-oriented && Process-oriented

Difference

面向过程，把所有事物看作一整个运行过程

面向对象，把所有事物看作一个个对象交互运行

Relationship diagram

Basic concepts of object-oriented php

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