Open new window with Response.Redirect() in Asp.net- 3rd part

In 2nd part of the following post I show you how to open a new window in asp.net using "ResponseHelper "class. Now today I want to share another approach with "Extension method".

Third approach(Extension method)

public static class ResponseHelper {

    public static void Redirect(this HttpResponse response,

        string url,

        string target,

        string windowFeatures) {

        if ((String.IsNullOrEmpty(target) ||

            target.Equals("_self", 
                       StringComparison.OrdinalIgnoreCase)) &&

                         String.IsNullOrEmpty(windowFeatures)) {

            response.Redirect(url);

        }

        else {

            Page page = (Page)HttpContext.Current.Handler;

            if (page == null) {

                throw new InvalidOperationException(

                    "Cannot redirect to new window outside
                    Page context.");

            }

            url = page.ResolveClientUrl(url);

            string script;

            if (!String.IsNullOrEmpty(windowFeatures)) {

                script = @"window.open(""{0}"", ""{1}"",
                                       ""{2}"");";

            }

            else {

                script = @"window.open(""{0}"", ""{1}"");";

            }

            script = String.Format(script, url, target,
                                   windowFeatures);

            ScriptManager.RegisterStartupScript(page,

                typeof(Page),

                "Redirect",

                script,

                true);

        }

    }

}

Note the 'this' keyword in the first parameter.
Now whenever we include the namespace this class
is defined within, we get a nice override on the
actual Response object.

Ex:

Response.Redirect("popup.aspx", "_blank", "menubar=0,width=100,height=100");