PHP中双冒号::的用法,php冒号用法
PHP中双冒号::的用法,php冒号用法
前几天在百度知道里面看到有人问PHP中双冒号::的用法,当时给他的回答比较简洁因为手机打字不大方便!今天突然想起来,所以在这里总结一下我遇到的双冒号::在PHP中使用的情况!
class test { static public $a; static public function b() {} }
如果要调用静态属性$a,如下
test::<span>$a</span>;
注意,a前面需要带$符号,这一点与->符号不一样!
如果要调用静态方法b,如下
test::b();
二,当调用自身类或者父类的属性或者方法时
首先建立一个父类
<span>class</span><span> test { </span><span>public</span> <span>function</span><span> b() {} }</span>
然后建立一个子类继承父类
<span>class</span> tests <span>extends</span><span> test { </span><span>public</span> <span>function</span><span> cs() {} }</span>
当我们需要调用父类的方法b时
parent::b();
self::cs();
<span>$this</span>->cs();
我遇到的大概就是以上两种情况,如果大家还遇到什么其他的情况,欢迎来王业楼的个人博客补充哈!
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