Detailed Explanation of php Magic Method

From PHP 5 onwards, classes in PHP can use magic methods. It stipulates that methods beginning with two underscores (__) are reserved as magic methods, so it is recommended that everyone's function name should not start with __, unless it is to overload existing magic methods. PHP keeps all class methods beginning with _ _ (two underscores) as magic methods.

__toString () and __invoke ()

public string __toString (void): This method is called automatically when the object is used as string. This method must return 1 string

<?php

    class Magic{

        public function  __tostring(){

            return "hello world!";

        }

    }

    $obj = new Magic();

    echo $obj;//hello world!

?>

__invoke (): This method is automatically called when the object is called as a method.

<?php

    class Magic{

        public function  __tostring(){

            return "hello world!";

        }

        public function __invoke($x){

            echo "__invoke called with param ".$x."\n";

        }

    }

    $obj = new Magic();

    $obj(10);//__invoke called with param 10 

?>

__call () and __callStatic ()

__call (): The __call () method is automatically called when an object accesses a method name that does not exist

__callStatic (): The __callStatic () method is automatically called when an object accesses a static method name that does not exist

Through these two methods, the call of the same method name can correspond to different method implementations

<?php

class Magic{

   //`$name`  Parameter is the name of the method to call. `$arguments`  The parameter is 1 Enumerated array, 

  // Contains the method to be passed to  `$name`  The parameters of the. 

        public function __call($name,$arguments){

            //implode()  Function to combine array elements into 1 Strings. implode(separator,array)

            echo "Calling " . $name ." with param: ".implode(", ",$arguments)."\n";

        }

    }

$obj = new Magic();

$obj->run("para1","para2");//obj To call run Method, output: Calling run with param: para1, para2   

?>

__get () and __set ()

When you assign a value to an inaccessible property, __set () is called
When reading the value of an inaccessible property, __get () is called

<?php

class Magic{

     //function  There must be before static Keyword 

    public function __get($name){

        return "Getting the property " . $name;

    }

}

$obj = new Magic();

echo $obj->className."\n";//Getting the property className 

?>

When reading the value of an inaccessible property, __get () is called

<?php

class Magic{
    public function __set($name,$value){

        echo "Setting the property " . $name ."to value ". $value ."\n";

    }

}

$obj = new Magic();

$obj->className = 'MagicClass';//Setting the property classNameto value MagicClass 

?>

__isset () and __unset ()

When you call isset () or empty () on an inaccessible property, __isset () is called
When unset () is called on an inaccessible property, __unset () is called

<?php

class Magic{

    public function __isset($name){

        echo "__isset invoked\n";

        return true;

    }

}

$obj = new Magic();

echo '$obj->className is set?'.isset($obj->className)."\n";//__isset invoked     $obj->className is set?1 

?>

Above is 8 php object-oriented magic method introduction and example, I hope you can help