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PHP catching all function calls

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Recently I came accross something really fancy that was introduced in PHP 5. It is appearantly possible for any class to catch all functions that are called on a class. So one function would catch $obj->callOne() as well as $obj->callTwo().

So why is this a nice feature to have, well because I am a very lazy progammer and this feature allows me to magically generate getters and setters. To do this I have the following setting for each class:

1. The constructor method __construct initializes an array containing the names of all variables that we want to store. We also create a second array to save the values in for the variables.
2. We implement the __call function to catch all functions being called on the object, which is currently still undocumented by PHP.net

So a basic class would look something similar to this:

class MyObject {
   private $my_vars = array();
   private $allowed_vars;

   function __construct() {
      $this->allowed_vars = array('var1', 'var2', 'var3');
   }

   function  __calls($function_name, $arguments) {
      $_variablename = substr($function_name, 3);
      if (array_search($_variablename, $this->allowed_vars) !== FALSE) {
         if (stripos($function_name, 'get') == 0 && stripos($function_name, 'get') !== FALSE) {
            return $this->my_vars[$_variablename];
         } else if (stripos($function_name, 'set') == 0 && stripos($function_name, 'set') !== FALSE) {
            $this->my_vars[$_variablename] = $arguments[0];
         }
      }
      else throw new Exception('Unkown function called on '. __CLASS__);
  }
}

Which does exactly that which I described above. Mind you it’s just a very basic example but it shows the power of a catch all function.

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