Check whether a user posted on facebook and twitter

We have an application written in C# .Net. We would like to offer our users free premium subscriptions to our services, in return for posting about us on twitter and Facebook.

To do that, currently, from inside our application, I simply open a browser component (Winforms WebBrowser), pointing to: "http://twitter.com/home?status=Check out..."

and after that to: "http://www.facebook.com/sharer.php?u=Our Company..."

and let the user perform the posts by himself.

Is there a way I cou开发者_Python百科ld make sure the user actually posted? Perhaps also check if the user indeed mentioned our company or changed the text we provided?

Thanks, Arie

The only way to truly be sure is to authenticate the user using OAuth and post to Twitter using POST statuses/update. For pretty good results though you can include a hashtag and use the Streaming API to track tweets containing the hashtag.