PHP & MySQL® Web Development All-in-One Desk Reference for Dummies®

4.11. Destroying Objects

You can destroy an object with the following statement:

unset($objName);

For example, you can create and destroy an object of the Car class with the following statements:

$myCar = new Car;
unset($myCar);

After $myCar is unset, the object no longer exists at all.

PHP provides a method that is automatically run when an object is destroyed. You add this method to your class and call it __destruct (with two underscores). For example, the following class contains a __destruct method:

class Bridge
{
  function __destruct()
  {
    echo "The bridge is destroyed";
  }
}

If you use the following statements, the object is created and destroyed:

$bigBridge = new Bridge;
unset($bigBridge);

The output from these statements is

The bridge is destroyed

The output is echoed by the __destruct method when the object is unset.

The __destruct method isn't required. It's just available for you to use if you want to execute some statements when the object is destroyed. For example, you might want to close some files or copy some information to your database.