how to make user come back to the same page after login

In asp.net 3.5, i am trying to send a user to a different https url to login, if the user is not logged in. I am kinda' restricting the user not to see the forum page in the current site (http://thisSite.com/forum.aspx), if the user is not logged in.

I am not sure how to redirect the user back from the login page (https://somethirdpartysite.com) back to the http://thisSite.com/forum.aspx

开发者_运维问答i tried placing response.redirect in my forum.aspx like this: response.redirect("https://somethirdpartysite.com"), but it's not behaving as expected.

Any pointers would help me.

Regards, Ron.

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Use ReturnUrl Query Strign key: https://somethirdpartysite.com?ReturnUrl=Forum.aspx so after the login an user will be automatically redirected to the Forum.aspx page.