How to call the _get function and _set function from external classes in PHP

The content of this article is to share with you about the method of calling _get function and _set function from external classes in PHP. There are detailed codes. I hope it can help friends in need.

Private attributes of external calling classes

First let’s take a look at the __get and __set functions in the PHP class
When trying to get an unavailable When the attribute is reached, the class will automatically call the __get function.
When trying to set an unreachable property, the class will automatically call the __set function.

First, let’s take a look at the __get function. Let’s try to get a reachable attribute:

<?php
    class A{
        public $a=1;
        private $b=2;
        function __get($name){
            echo &#39;you can get &#39;.$name;
        }
    }
    $dy = new A();
    echo $dy->a;
?>

Look at its return:

1

No problem, the __get function is not called. Now I will access a private unreachable attribute:

<?php
    class A{
        public $a=1;
        private $b=2;
        function __get($name){
            echo &#39;you can get &#39;.$name;
        }
    }
    $dy = new A();
    echo $dy->b;
?>

and I will find:

you can get b

It means __get is called here function, let me take a look at the __set function, which also uses the reachable public attribute first:

<?php
    class A{
        public $a;
        private $b;
        function __set($name,$val){
            echo &#39;you can get &#39;.$name.$val;
        }
    }
    $dy = new A();
    $dy->a = 1;
    echo $dy->a;
?>

Look at the output:

1

Used successfully, no problem, then we use private attributes:

<?php
    class A{
        public $a;
        private $b;
        function __set($name,$val){
            echo &#39;you can get &#39;.$name.$val;
        }
    }
    $dy = new A();
    $dy->b = 1;
    echo $dy->b;
?>

At this time we see:

you can get b1

PHP Fatal error:  Cannot access private property A::$b in /usercode/file.php on line 11

The __set function is called here and prompts us that we cannot use it Private properties of the class.
Now let’s use the __set function to implement external use of private attributes:

<?php
    class A{
        public $a;
        private $b;
        function __set($name,$val){
                $this->$name=$val;
        }
        function B(){
            echo $this->b;
        }
    }
    $dy = new A();
    $dy->b = 1;
    $dy->B();
?>

Look at the output:

1

It means the use is successful.

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