php 魔术方法

__tostring 将对象当字符串输出

__invoke 将对象当方法输出

例子：

class Test{

    public function __tostring(){

        return 'this is test
';

    }

    public function __invoke($x){

        echo 'params is methed '.$x;

    }

}

$obj = new Test();

echo $obj;

$obj(6);

方法的重载：当类中没有此方法时候调用的魔术方法

$name：方法的名称

$arguments:方法中参数组成的数组

__call($name,$arguments)

__callStatic($name,$arguments)

例子：

class Test{

    public function __call($name,$arguments){

        echo "call===".$name.'====with parameters:'.implode(',',$arguments)."
";

    }

    public static function __callStatic($name,$array){

        echo "static calling===".$name.'====with parameters:'.implode(',',$array)."\n";

    }

}

$obj = new Test();

$obj->runTest('param');

Test::runTest('param1','param2');

属性重载:对未定义属性的操作

__get($name)

__set($name,$value)

__isset($name)

__unset($name)

例子

class Test{

    public function __get($name){

        echo 'Getting the property '.$name.'
';

    }

    public function __set($name,$value){

        echo 'Setting the property '.$name.' to value '.$value.'
';

    }

    public function __isset($name){

        echo "__setting invoke
";

        return true;

    }

    public function __unset($name){

        echo "Unset property {$name}
";

    }

}

$obj = new Test();

$obj->classname;

$obj->classname = 'TestValue';

echo '$obj->classname is set?'.isset($obj->classname).'
';//取决返回值是true还是false

unset($obj->classname);

 

__clone:只想修改当前类的某些数据，不影响当前类的时候调用

例子

class Test{

    public $name;

    public   function __clone(){//当权限为privite和protected权限时，外部不可用clone函数

        $this->name = 'TBD';

    }

}

$obj = new Test();

$obj->name = 'james';

echo $obj->name.'
';

$obj2 = clone $obj;

echo 'before set up:$obj2: '.$obj2->name.'
';

$obj2->name = 'james2';

echo 'james: '.$obj->name.'
';

echo 'james2: '.  $obj2->name.'
';