[SOLVED] Request.URL doubles query string parameters?

Request.URL doubles query string parameters?

I request a URL like this:

http://mylocalsite/virtual/page.aspx?var1=1&var2=2&var3=3

I'm using FormsAuthentication and am unauthenticated, so I'm redirected. This is what the browser location bar shows:

http://mylocalsite/virtual/login.aspx?ReturnUrl=/virtual/page.aspx?var1=1&var2=2&var3=3

In the PageLoad event of login.aspx I try to inspect the URL two ways:

Dim example1 as String = Request.Url

Dim example2 as String = Request.Url.Scheme & "://" & Request.Url.Authority & Request.RawUrl

This is what I get:

' Example 1
http://mylocalsite/virtual/login.aspx?ReturnUrl=/virtual/page.aspx?var1=1&var2=2&var3=3&var1=1&var2=2&var3=3

' Example 2 - is URLEncoded
http://mylocalsite/virtual/login.aspx?ReturnUrl=%2fvirtual%2fpage.aspx%3fvar1%3d1%26var2%3d2%26var3%3d3%26var1%3d1%26var2%3d2%26var3%3d3

Why is my query string doubling up in both of these examples?

Solution

This is done by design so you have access to those querystring parameters during login. Those parameters must also be preserved for redirect post-login too - so they are url encoded as well. See the Anatomy of Forms Authentication ReturnUrl for a more detailed explanation.