AS2 → AS3: LoadVars AS3 Equivalent

ActionScript 3 has done away with the LoadVars class and when I was updating my ContactForm for AS3 I was trying to figure out how to mimic the sendAndLoad() method that LoadVars provided. I stumbled upon an article by Peter Elst which explained how to do this so I'm going to outline the differences here.

 

Let's take a look at the old AS2 code:

 

 

Actionscript:

1. var msg:LoadVars = new LoadVars();
2. var msgSent:LoadVars = new LoadVars();
3.  
4. msg.var1 = "one";
5. msg.var2 = "two";
6.        
7. msgSent.onLoad = function($success:Boolean):Void
8. {
9.     if ($success)
10.     {
11.         trace("Message sent.");
12.     }
13.     else
14.     {
15.         trace("Message failed.");
16.     }
17. };
18.  
19. msg.sendAndLoad("http://www.reintroducing.com/script.php", msgSent); 

 

 And here is the AS3 equivalent:

 

Actionscript:

1. var scriptRequest:URLRequest = new URLRequest("http://www.reintroducing.com/script.php");
2. var scriptLoader:URLLoader = new URLLoader();
3. var scriptVars:URLVariables = new URLVariables();
4.  
5. scriptLoader.addEventListener(Event.COMPLETE, handleLoadSuccessful);
6. scriptLoader.addEventListener(IOErrorEvent.IO_ERROR, handleLoadError);
7.  
8. scriptVars.var1 = "one";
9. scriptVars.var2 = "two";
10.    
11. scriptRequest.method = URLRequestMethod.POST;
12. scriptRequest.data = scriptVars;
13.  
14. scriptLoader.load(scriptRequest);
15.  
16. function handleLoadSuccessful($evt:Event):void
17. {
18.     trace("Message sent.");
19. }
20.  
21. function handleLoadError($evt:IOErrorEvent):void
22. {
23.     trace("Message failed.");
24. }

 

As you can see, there is a new URLVariables class that stores the information you want to pass to your script. You then pass that URLVariables instance to the URLRequest's data property. Essentially, what this does, is create a query string with all the variables appended to it. The above actually looks like this when it is sent to the server:

http://www.reintroducing.com/script.php?var1=one&var2=two

That is what the PHP script receives and then handles it on the script's end to do whatever it is that you are wanting to do. I also explicitly set the URLRequest's method to be POST by setting the URLRequestMethod.POST constant (for GET, you'd just set URLRequestMethod.GET).

 

 

http://evolve.reintroducing.com/2008/01/27/as2-to-as3/as2-%E2%86%92-as3-loadvars-as3-equivalent/