What does double colon mean in php

What does the double colon mean in php?

First, when calling static properties and static methods

::and-> The function is the same, but the objects used are different! ::Refer to static methods or properties in the class, and no instantiation is required!

Create a class, and create a static property $a and a static method b, as follows:

class test {
    static public $a;
    static public function b() {}
}

If you want to call the static property $a, as follows

test::$a;

Note that a needs to be preceded by the $ symbol, which is different from the -> symbol!

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

class test {
    public function b() {}
}

Then create a subclass to inherit the parent class

class tests extends test {
    public function cs() {}
}

When we need to call the parent class’s method b

parent::b();

When we need to call our own method cs , there are two methods

$this->cs();
self::cs();

For more related tutorials, please pay attention tophp中文网!

The above is the detailed content of What does double colon mean in php. For more information, please follow other related articles on the PHP Chinese website!