ASP.NET Persist POST data through login redirect

Question

I have a site (SiteA) using ASP.NET membership. One thing that it must do is allow the end user at a separate site (SiteB) to launch a new browser window to a page at SiteA with POST data attached to prefill the page.

If the user is logged into SiteA, then the launch from SiteB works and the page is prefilled. However, if the user is not logged in, SiteA's authentication redirects to the login page first. After logging in the user is redirected to the final page, but the POST data is lost and the form is not prefilled.

How can I persist the POST data to the final page?

Answer 1

Sounds like a job for the Cookie Monster. Either set a cookie or a session state var.

cookies

where i learned cookies

session state variables