Query string: Can a query string contain a URL that also contains query strings?

Question

Example:

http://foo.com/generatepdf.aspx?u=http://foo.com/somepage.aspx?color=blue&size=15

I added the iis tag because I am guessing it also depends on what server technology you use?

Answer 1

The server technology shouldn't make a difference.

When you pass a value to a query string you need to url encode the name/value pair. If you want to pass in a value that contains a special character such as a question mark (?) you'll just need to encode that character as %3F. If you then needed to recursively pass another query string to the encoded url, you'll need to double/triple/etc encode the url resulting in the original ? turning into %253F, %25253F, etc.