How Can I Create a True Copy of a PHP Object?

Diving into Object Cloning in PHP

When working with objects in PHP, it's important to understand that they are inherently passed by reference. This means that any changes made to an object within a function will also affect the original object. This behavior can be both advantageous and disadvantageous depending on the situation.

In your specific example, you'd expect the assignment $c = $a to create a copy of the object $a. However, since objects are passed by reference, $c actually points to the same object as $a. Thus, the subsequent call to set_b($a) modifies both $a and $c, as they are effectively the same object.

To truly create a copy of an object in PHP, you need to use the clone operator. This operator creates a new object with the same properties and values as the original, but with a different memory address. By using the clone operator, you can ensure that changes made to the cloned object will not affect the original.

Here's how you can implement cloning in your code:

$objectB = clone $objectA;

This line will create a new object $objectB that is a copy of $objectA. Any changes made to $objectB will not affect $objectA, and vice versa.

It's worth noting that not all objects can be cloned. Objects that have circular references or implement the __clone() method may not be able to be copied correctly. In such cases, you may need to manually create a copy of the object by assigning each property individually.

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