Zend Preparation | PHP Quiz (Learning Mode)

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You run the following PHP script:

<?php 
class Test {
  function __call( $var1, $var2 ) {
          $check = " '$var1' called\n";
          $check.= print_r( $var2, true );
       return $check;
     }
}
$item = new Test();
print $item->array( "John", "Maria", "Jason" );
?>

What is the work of the __call() method in the above script?

To define undefined objects

To catch undefined objects

To catch undefined variables

To catch undefined methods

Explanation: Answer option D is correct.

The __call() method is the magic method in PHP 5 that is triggered when inaccessible methods are triggered in an object context. If a user defines the __call() method in the class, he can catch undefined/inaccessible method and decide what to do with it. There are two arguments that are automatically passed to the __call() method, i.e., a string variable holding the name of the method that was called and an array variable holding any arguments that were passed. In the above script, you have created a class called Test and given it a __call() method. The __call() method accepts the method name and an array of method arguments. It assigns a string quoting the contents of both of these to a variable, $check, and returns it to the calling code. Hence, in the above PHP code, it will catch the nonexistent $item->array() method and print the result:

 'array' called
Array ( [0] => John [1] => Maria [2] => Jason )