PHP對象複製clone用法樣本

本文執行個體講述了PHP對象複製clone用法。分享給大家供大家參考，具體如下：

淺複製：只是複製對象中的非對象非資源資料，即對象中屬性儲存區的是物件類型，則會出現複製不完全

<?phpclass B{ public $val = 10;}class A{ public $val = 20; public $b; public function __construct(){  $this->b = new B(); }}$obj_a = new A();$obj_b = clone $obj_a;$obj_a->val = 30;$obj_a->b->val = 40;var_dump($obj_a);echo '<br>';var_dump($obj_b);

運行結果如下：

object(A)[1] public 'val' => int 30 public 'b' => object(B)[2]  public 'val' => int 40 object(A)[3] public 'val' => int 20 public 'b' => object(B)[2]  public 'val' => int 40

深複製：一個對象的所有屬性資料都徹底的複製，需要使用魔術方法__clone()，並在裡面實現深度複製

<?phpclass B{ public $val = 10;}class A{ public $val = 20; public $b; public function __construct(){  $this->b = new B(); } public function __clone(){  $this->b = clone $this->b; }}$obj_a = new A();$obj_b = clone $obj_a;$obj_a->val = 30;$obj_a->b->val = 40;var_dump($obj_a);echo '<br>';var_dump($obj_b);

運行結果如下：

object(A)[1] public 'val' => int 30 public 'b' => object(B)[2]  public 'val' => int 40 object(A)[3] public 'val' => int 20 public 'b' => object(B)[4]  public 'val' => int 10

希望本文所述對大家PHP程式設計有所協助。