IIS 7.5 with URL Rewrite Module Doubles QueryString Params on Postback

Question

Hi

I'm using IIS 7.5 on Windows 7 RC. I use the IIS Url Rewrite module to rewrite URLs.

Everything seems to work fine, until I perform a postback by clicking a button. It then appends the querystring params to my rewritten URL, like this:

Rewritten URL, as it appears in the browser: http://localhost/en/product/1239/Gary+Fisher+Hkek+Mountain+Bike

Without URL rewriting the URL is:

http://localhost/product.aspx?lang=en&id=1239&title=Gary+Fisher+Hkek+Mountain+Bike

When I click a button to perform a postback, the URL changes to this:

http://localhost/en/product/1239/Gary+Fisher+Hkek+Mountain+Bike?lang=en&id=1239&title=Gary+Fisher+Hkek+Mountain+Bike

And when the URL is rewritten, all querystring params are doubled - so when I want to get the current language by doing this:

Request.QueryString["lang"]

The value I get back is "en,en".

Is anyone else having those problems?

UPDATE: Rewrite rules from Web.Config

<rule name="RedirectProductPageUrls" stopProcessing="true">
 <match url="^product\.aspx$" />
 <conditions logicalGrouping="MatchAll">
  <add input="{REQUEST_METHOD}" negate="true" pattern="^POST$" />
  <add input="{QUERY_STRING}" pattern="^lang=([^=&amp;]+)&amp;id=([^=&amp;]+)&amp;title=([^=&amp;]+)$" />
 </conditions>
 <action type="Redirect" url="{C:1}/products/{C:2}/{C:3}" appendQueryString="false" redirectType="Permanent" />
</rule>
<rule name="RewriteProductPageUrls" stopProcessing="true">
 <match url="^([^/]+)/product/([^/]+)/([^/]+)/?$" />
 <conditions logicalGrouping="MatchAll">
  <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
  <add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
 </conditions>
 <action type="Rewrite" url="product.aspx?lang={R:1}&amp;id={R:2}&amp;title={R:3}" />
</rule>

Answer 1

ı have the same problem, please help :(

Answer 2

Add the appendQueryString="false" attribute to the action element of the rewrite rule as well.

Hope this helps.

György Balássy

Answer 3

This is a security feature of the IIS Rewrite Module.

I personally prefer ISAPI Rewrite as it is much better, simpler to write rules, and has more features.

Have also found under moderate to high load (over 100 connections to a website) that the IIS Rewrite Module courses the application pool to crash and spawn and new process.

Answer 4

appendQueryString="false" does NOT solve the problem in all cases... If you need to the ability to append to the query string and post back on the same page then at this point the IIS rewrite module is unusable in IIS 7.5. I have spent the last few days looking for a solution, and I not yet come across any form of a solution that works for all of my rewritten pages.

If the issue is a security problem please let everyone how to disable the "feature" to fix the issue.

Answer 5

I was able to solve the issue by adding

Form.Action = Request.RawUrl;

to the Page_Load event. I was able to leave appendQueryString="TRUE" and so far it is working properly.