Wade Arnold

Type Cast objects coming back in AMF are mx.utils::ObjectProxy and are capable of becoming the object type that you specified. However we don’t want to JUST ASSume that you are getting the correct object type back. It takes a small amount of work. In order to change the ObjectProxy into the proper data type.I recommend that you wrap your result into a try catch before you just assume that you have received the correct data.

private function onResult(event:ResultEvent):void{
  try {
    var myContact:ContactVO = event.result as ContactVO;
    trace('name' +myContact.firstname);
  }
  catch(error: Error) {
    trace('onResult error: ' + error.message);
  }
}

Yes you could just Jam the type into a value.

var myContact:ContactVo = ContactVO(event.result);

But if something didn’t work out on the server and you get a successful result your application just crashed because you have a type correlation exception.

or as Ivan Erickson Suggested:

private function onResult(event:ResultEvent):void{
  try {
    var myContact:ContactVo = ContactVO(event.result);
    trace('name' +myContact.firstname);
  }
  catch(error: Error) {
    trace('onResult error: ' + error.message);
  }
}

if you’re not going to null check the return from var and save the CPU cycle for the as().. thanks Ivan!

Joel Caspers a new T8DESIGN stud also says:
Also, you can remove the need for try-catch statement entirely by using the is operator in an if statement – in my experience try catch statements are processor costly and I’ve always been instructed to stay away from them, as well as you could be catching an error that you are not intending to catch (something other than the cast error inside your try statement).

If (event.result is ContactVO) {
   //it is what you think it is
   Var myContact:ContactVO = ContactVO(event.result);
} else {
  //the result is not what you think it is so spit out the type in the console
   Trace(getQualifiedClassName(event.result));
}

Hope that this helps!

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