Usage of double colon:: in PHP, php colon usage_PHP tutorial
Usage of double colon:: in PHP, usage of colon in php
A few days ago, I saw someone on Baidu Zhizhi asking about the usage of double colon:: in PHP, and I gave it to him at that time The answer is relatively concise because it is not convenient to type on a mobile phone! It suddenly occurred to me today, so here is a summary of the situations I encountered using double colon:: in PHP!
class test {
static public $a;
static public function b() {}
}
If you want to call the static property $a, as follows
test::<span>$a</span>;
Note that a needs to be preceded by a $ sign, which is different from the -> sign!
If you want to call static method b, as follows
test::b();
2. When calling attributes or methods of your own class or parent class
First create a parent class
<span>class</span><span> test { </span><span>public</span> <span>function</span><span> b() {} }</span>
Then create a subclass that inherits the parent class
<span>class</span> tests <span>extends</span><span> test { </span><span>public</span> <span>function</span><span> cs() {} }</span>
When we need to call method b of the parent class
parent::b();
self::cs();
<span>$this</span>->cs();
What I encountered are probably the above two situations. If you encounter any other situations, you are welcome to come to Wang Yelou’s personal blog to add them!
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