what is Object Cloning in php?

Question

Can someone explain me

• what is Object Cloning in php?

• When should i use clone keyword in php?

Answer 1

Cloning is used to create a genuine copy of an object. Assigning an object to another variable does not create a copy - rather, it creates a reference to the same memory location as the object:

a= 'b';
$o->b= 'c';

$o2= $o;
$o2->a= 'd';

var_dump($o);
var_dump($o2);

$o3= clone $o;
$o3->a= 'e';
var_dump($o);
var_dump($o3);

?>

This example code will output the following:

object(stdClass)#1 (2) {
  ["a"]=>
  string(1) "d"
  ["b"]=>
  string(1) "c"
}
object(stdClass)#1 (2) {
  ["a"]=>
  string(1) "d"
  ["b"]=>
  string(1) "c"
}
object(stdClass)#1 (2) {
  ["a"]=>
  string(1) "d"
  ["b"]=>
  string(1) "c"
}
object(stdClass)#2 (2) {
  ["a"]=>
  string(1) "e"
  ["b"]=>
  string(1) "c"
}