PHP Magic Method __clone __tostring (v)

__clone ()-Automatically load this method when the object is cloned

__tostring ()-Automatically loads this method when an object needs an echo print output

__clone ()

<?phpclass example{public    static $PA;    public $PB;    Public Function __construct () {        $this->PB = ++self:: $pa;    }        Public Function __clone () {        $this->PB = ' no Zuo no die ';    }} $a = new example; $b = new example; $c = Clone $b; $b->pb = ' I love your so much! '; echo $a->pb;echo ' 
The results are as follows
1------------------------------------------------------------------------------------I Love much! ------------------------------------------------------------------------------------No Zuo no die/* if there is __ Clone () This magic method, the result of this side should be 2*/-------------------------------------------------------------------------------- ----I Love much!
The PHP manual gives us an example that is somewhat difficult to read, as follows
<?phpclass subobject{    static $instances = 0;    public $instance;    Public Function __construct () {        $this->instance = ++self:: $instances;    }    Public Function __clone () {        $this->instance = ++self:: $instances;    }} Class mycloneable{public    $object 1;    Public $object 2;    function __clone ()    {              //forces a copy of This->object, otherwise it still points to the same object        $this->object1 = Clone $this Object1;}    } $obj = new Mycloneable (), $obj->object1 = new Subobject (), $obj->object2 = new Subobject (), $obj 2 = Clone $obj;p rint ("O Riginal object:\n ");p Rint_r ($obj);p rint (" Cloned object:\n ");p Rint_r ($obj 2);? >
The final result
OriginalObject: MycloneableObject([Object1]= SubobjectObject([instance]=1) [Object2]= SubobjectObject([instance]=2)) ClonedObject: MycloneableObject([Object1]= SubobjectObject([instance]=3/ * may be more difficult to understand here, in fact, $obj2 when cloning the final instance as 2 of the result of cloning, and then execute the Subobject::__clone method *  /) [Object2]= SubobjectObject([instance]=2        ))
__tostring ()
<?php//Declare A simple classclass testclass{public    $foo;    Public function __construct ($foo)     {        $this->foo = $foo;    }    Public Function __tostring () {        return $this->foo;    }} $class = new TestClass (' Hello '); Echo $class;? >
Results
Hello
PHP Magic Method __clone __tostring (v)