301 Canonical Redirects in ASP.net MVC

MVC301.cs

protected void Application_BeginRequest(Object sender, EventArgs e)
{
    if (Request.Url.Authority.StartsWith("www"))
        return;
 
    string url = (Request.Url.Scheme
        + "://www."
        + HttpContext.Current.Request.Url.Authority
        + HttpContext.Current.Request.Url.AbsolutePath
    );
 
    Response.Clear();
    Response.Status = "301 Moved Permanently";
    Response.AddHeader("Location", url);
    Response.End();
}