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php面向对象有关

Jun 13, 2016 pm 12:32 PM
define final function php self

php面向对象相关

php构造方法 function__constructz(){

}

php5中带的析构函数function__destruct(){}//不能带有任何参数

static 可以声明静态的方法,静态的属性。这是存在在内存中的。

php中 类中静态的方法只能访问静态的属性,非静态的方法只能访问非静态的属性。

self? 和$this类似,但是self是调用静态属性用的,self::属性名(不指向任何实例化的对象)

final? 用来定义类和方法 不能用来定义成员属性。因为final是定义常量的,php中定义常量是define();final定义的类不能被继承。使用final标记的方法也不能被覆盖。

define()定义常量使用的是这个函数。

const 在类中定义常量的关键字。

__toString()? 如果在类中写上这个,那么echo就可以正确的打印出对象(也就是引用哪个类$pag = new animal())值。

__clone? 克隆? 一个有相同属性的函数。

__call() 这个是吸错的方法,在类里面写上这个方法,那么我们调用类里面的不存在的方法就会提示错误,但是程序继续运行。

__autoload() 自动加载? 在开发的时候很多时候要include 加载一些文件,如果用这个方法那么就不用这么麻烦了,再用到的时候就会自动加载

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