Question

When using the System.Windows.Forms.WebBrowser control, is there a way to control which version of IE rendering engine it will use?

Answer 1

I believe IE does this by manipulating the request User-Agent string.

compatible; MSIE 7.0;
compatible; MSIE 8.0;
compatible; MSIE 9.0;

So to use different rendering engines with WebBrowser you would need to do something similar. Unfortunately getting access to the User-Agent in WebBrowser is not easy. You can do it if you extend the actual Com component, rather than using the .Net control.

public class ExtendedWebBrowser : WebBrowser
{
    ...

    void BeforeNavigate(object pDisp, ref object url, ref object flags,
                       ref object targetFrameName, ref object postData, 
                       ref object headers, ref bool cancel)
    {
         if (!headers.Contains("X-RequestFlag")
         {
             headers += "X-RequestFlag: true\r\n";

             // append user-agent header here
             headers["User-Agent"] = ...;

             // cancel current request
             cancel = true;

             // re-request with amended details
             Navigate((string)url, (string)targetFrameName, (byte[])postData, 
                      (string)headers);
         }
         else
         {
             base.BeforeNavigate(...);
         }
    }
}