Explain the Magic Method in Detail
The function names __construct(), __destruct(), __call(), __callStatic(), __get(), __set(), __isset(), __unset(), __sleep(), __wakeup(), __toString(), __invoke(), __set_state(), __debugInfo() and __clone() are magical in PHP classes.
1) You cannot create any usr-defined function with double underscore (i.e __) because double underscore is reserved.
2) Magic Methods are start with double underscore (i.e __).
3) When we create any magic method in class start calling automatically. that's why called magic method.
__construct
When we make init an class object, It will call __construct method.
__destruct
When class scope end, It will call __destruct method.
__call
When we make trying to access inaccessible methods, It will call the __call method.
__callStatic
When we make trying to access inaccessible methods in static, It will call the __callStatic method.
__get
When we make trying to access inaccessible variable, It will call the __get method.
__isset()
When we make trying to calling isset() or empty() on inaccessible properties, It will call the __isset method.
__unset()
When we make trying to calling unset on inaccessible properties, It will call the __unset method.
__sleep()
When we are using serialize() function, It will check for __sleep(). If __sleep() is defined, this function is executed prior to any serialization.
__wakeup()
When we are using unserialize() function, It will check for __wakeup(). If __wakeup() is defined, this function is executed prior to any unserialization.
__toString()
When we try to print an object, It will call __toString() function (if defined).
__invoke()
When we try to call object as function, It will call __invoke() function (if defined).
__set_state()
When we are using var_export() function, It will check for __set_state(). If __set_state() is defined, this function is executed prior to any var_export().
__debugInfo()
When we are using var_dump() function, It will check for __debugInfo. If __debugInfo is defined, this function is executed prior to any var_dump().
Example of __sleep and __wakeup:
/** class to test magic method i.e sleep and wakeup **/
class magicmethod
{
public $name1 = 'Hello';
function __wakeup() {
echo "__wakeup funx called \n";
echo $this->name1;
}
function __sleep(){
echo "__sleep funx called \n";
$this->name1 ='Arun kumar';
return array('name1');
}
}
$obj = new magicmethod();
$objString = serialize($obj);
echo $objString;
echo '\n' ;
unserialize($objString);
Output
__sleep funx called
O:11:"magicmethod":1:{s:5:"name1";s:10:"Arun kumar";}
__wakeup funx called
Arun kumar
