Post-Redirect-Get with Internet Explorer

Question

I have a web page that implements the post/redirect/get pattern to avoid double posts in a simple CRUD application.

The intended request/response sequence here is:

1. browser sends data via POST
2. server modifies the DB, responds with status 302 Moved Temporarily and a Location header
3. browser follows the redirect via GET
4. server responds with the updated page

This is how it is supposed to work – and it does, in Chrome for example.

Internet Explorer 9, however, sends step 3 as a POST, too (including the complete set of form data!). Why? What should I do to make it use GET?

I should add that apart from the query string the redirect goes to the same location as the form target.

I've tried:

• all available of rendering modes (IE7, IE8, IE9, Quirks, Standards, Compat)
• a full DOCTYPE
• a relative URL or an absolute one in the Location header
• HTTP Status 303 (just to see if that makes any difference)

Answer 1

The correct status code if you want a GET is 303, although 301 and 302 will also do what you want in common browsers.

If this is not working, something else probably is wrong. An HTTP trace would be helpful for finding what is wrong.

Answer 2

I'm not sure but it seems like IE9 doesn't actually sent "POST" after redirect 30x - it just displays it in his internal debugger.