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phpconstructormultiple-constructors

Calling another constructor from a constructor in PHP


I want a few constructors defined in a PHP class. However, my code for the constructors is currently very similar. I would rather not repeat code if possible. Is there a way to call other constructors from within one constructor in a php class? Is there a way to have multiple constructors in a PHP class?

function __construct($service, $action)
{
    if(empty($service) || empty($action))
    {
        throw new Exception("Both service and action must have a value");
    }
    $this->$mService = $service;
    $this->$mAction = $action;

    $this->$mHasSecurity = false;
}
function __construct($service, $action, $security)
    {
        __construct($service, $action); // This is what I want to be able to do, so I don't have to repeat code

        if(!empty($security))
        {
            $this->$mHasSecurity = true;
            $this->$mSecurity = $security;
        }
    }

I know that I could solve this by creating for instance some Init methods. But is there a way around this?


Solution

  • You can't overload functions like that in PHP. If you do this:

    class A {
      public function __construct() { }
      public function __construct($a, $b) { }
    }
    

    your code won't compile with an error that you can't redeclare __construct().

    The way to do this is with optional arguments.

    function __construct($service, $action, $security = '') {
      if (empty($service) || empty($action)) {
        throw new Exception("Both service and action must have a value");
      }
      $this->$mService = $service;
      $this->$mAction = $action;
      $this->$mHasSecurity = false;
      if (!empty($security)) {
        $this->$mHasSecurity = true;
        $this->$mSecurity = $security;
      }
    }