how to get selected friend ids from multi-friend-selector?

I am developing a new facebook application in .net c#, I want to select some friends and and do post them something in another page my code is below:

<fb:request-form type="Use ASP.NET" invite="true" method="POST" action="http://apps.facebook.com/gcmobtest/" content="Let&#39;s use ASP.NET together!<fb:req-choice url='http://apps.facebook.com/gcmobile/' label='Start using ASP.NET now!' />">
    <fb:multi-friend-selector actiontext="Share this ASP.NET sample with your friends!" showborder="true" r开发者_JAVA技巧ows="5" />
</fb:request-form>

I want to get a list of friends ids and do something by them when user click on send button. I`ll be grateful if someone guide me what code an write it where

this application is similar to what i want to do http://apps.facebook.com/special-gcards/

Facebook will do a POST to the URL you specific in the form (http://apps.facebook.com/gcmobtest/). The POST will have a field called "ids" that will contain the user IDs that were selected. http://developers.facebook.com/docs/reference/fbml/multi-friend-input/

Facebook has released a non-FBML version (javascript) of the the friend request that returns the IDs directly, if any were selected. http://developers.facebook.com/docs/reference/dialogs/requests/

In typical Facebook fashion, they released v1.0 on Jan 26 (http://developers.facebook.com/blog/post/453) and released 2.0 on Feb 16 (http://developers.facebook.com/blog/post/464).