Handling Postbacks in ASP.Net while using UrlRewriting

Handling Postbacks

If the URLs you are rewriting contain a server-side Web Form and perform postbacks, when the form posts back, the underlying URL will be used. That is, if our user enters into their browser, /Products/Beverages.aspx, they will still see in their browser's Address bar, /Products/Beverages.aspx, but they will be shown the content for ListProductsByCategory.aspx?CategoryID=1. If ListProductsByCategory.aspx performs a postback, the user will be posted back to ListProductsByCategory.aspx?CategoryID=1, not /Products/Beverages.aspx. This won't break anything, but it can be disconcerting from the user's perspective to see the URL change suddenly upon clicking a button.
The reason this behavior happens is because when the Web Form is rendered, it explicitly sets its action attribute to the value of the file path in the Request object. Of course, by the time the Web Form is rendered, the URL has been rewritten from /Products/Beverages.aspx to ListProductsByCategory.aspx?CategoryID=1, meaning the Request object is reporting that the user is visiting ListProductsByCategory.aspx?CategoryID=1. This problem can be fixed by having the server-side form simply not render an action attribute. (Browsers, by default, will postback if the form doesn't contain an action attribute.)
Unfortunately, the Web Form does not allow you to explicitly specify an action attribute, nor does it allow you to set some property to disable the rendering of the action attribute. Rather, we'll have to extend the System.Web.HtmlControls.HtmlForm class ourselves, overriding the RenderAttribute() method and explicitly indicating that it not render the action attribute.
Thanks to the power of inheritance, we can gain all of the functionality of the HtmlForm class and only have to add a scant few lines of code to achieve the desired behavior. The complete code for the custom class is shown below:

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namespace ActionlessForm {
  public class Form : System.Web.UI.HtmlControls.HtmlForm
  {
     protected override void RenderAttributes(HtmlTextWriter writer)
     {
        writer.WriteAttribute("name", this.Name);
        base.Attributes.Remove("name");

        writer.WriteAttribute("method", this.Method);
        base.Attributes.Remove("method");

        this.Attributes.Render(writer);

        base.Attributes.Remove("action");

        if (base.ID != null)
           writer.WriteAttribute("id", base.ClientID);
     }
  }
}

The code for the overridden RenderAttributes() method simply contains the exact code from the HtmlForm class's RenderAttributes() method, but without setting the action attribute. (I used Lutz Roeder's Reflector to view the source code of the HtmlForm class.)
Once you have created this class and compiled it, to use it in an ASP.NET Web application, start by adding it to the Web application's References folder. Then, to use it in place of the HtmlForm class, simply add the following to the top of your ASP.NET Web page:

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<%@ Register TagPrefix="skm" Namespace="ActionlessForm" 
   Assembly="ActionlessForm" %>

Then, where you have

, replace that with:

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and replace the closing
tag with:

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Redirect HTTP to HTTPS with IIS 7

Getting onto two years ago now I wrote an article that has become quite popular that detailed three methods to redirect HTTP to HTTPS. At that time there wasn't a lot in the way of options for URL manipulation on IIS, and Helicon's ISAPI Rewrite 2 was the de facto standard. Now there are several options for rewriting URL's on IIS, and users of IIS 7 are able to take advantage of Microsoft's own URL Rewrite module. In this guide we'll look at how you can use Microsoft's URL rewrite module to transparently redirect HTTP to HTTPS.

For this guide to work you'll need;

• 
  IIS 7 installed
• 
  Microsoft URL Rewrite Module installed
• 
  Create HTTPS bindings to your IIS website and assign certificate
• 
  Ensure Require SSL is NOT checked under SSL Settings for your website

Once you have this done you can simply copy and paste the following code between the <rules> and </rules> tags in your your web.config file in your website root directory.

<rule name="HTTP to HTTPS redirect" stopProcessing="true">

  <match url="(.*)" />

    <conditions>

      <add input="{HTTPS}" pattern="off" ignoreCase="true" />

    </conditions>

  <action type="Redirect" redirectType="Found" url="https://{HTTP_HOST}/{R:1}" />

</rule>

From here all you have to do is save your web.config file and test that the redirection is working. Hopefully this guide has helped you to enabled HTTP to HTTPS redirection for your website on IIS 7 using the Microsoft URL Rewrite Module. If you have any feedback or comments please post below, and if you have specific support requests please post in the forums