ASP.NET [Facebook API] - Reading a signed_request with C# (given only as PHP in fb docs as PHP)

How? I tried everything, I couldn't do it. All I see is PHP code, I tried browsing through stackoverflow, tri开发者_如何学编程ed searching online (google, yahoo, etc.), but no where did I find an answer. I saw some post here saying to use:

string requested_Data = Request.Form["signed_request"];
var DecodedSignedRequest = FacebookSignedRequest.Parse(appSecret, requested_Data);

Unfortunately, requested_Data always returns null (and no, it is not a redirect). I'm not even sure if the second line works since I can't even get past the first line. I tried

Request.QueryString.Get("signed_request");

and it did not work... What is the problem with requested_Data always being null? Please assist!

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did you try putting Html.FacebookSignedRequest() into your form? What is the form action to? Are you using MVC? Post some code to see if we can figure it out

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Make sure that you have setup config values correctly for facebook in config file. (APPID, APPSECRET etc.) Also did you try using Request.Param["signed_request"]; instead?

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var signedReuest = FacebookWebContext.Current.SignedRequest;

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You might find that you didn't set up an app on Facebook. If you ONLY set up a 'Page Tab', the signed request never gets sent. This drove me nuts for ages. If you want to program a fan gate you MUST set up your app to be both a 'Page Tab' and an 'App on Facebook'