301 redirect using global.asax.cs

Below is code to do 301 redirect using the global.asax.cs file.

protected void Application_BeginRequest(object sender, EventArgs e)
{
    string s1 = "http://www.yourwebsite.com/oldurl.old";
    string sRedirect = "http://www.yourwebsite.com/newurl";
    if (HttpContext.Current.Request.Url.ToString().ToLower().Contains(s1))
    {
            string sNewPage = Request.Url.ToString().ToLower().Replace(s1, sRedirect);
            Response.Clear();
            Response.Status = "301 Moved Permanently";
            Response.AddHeader("Location", sNewPage);
            Response.End();
    }
    //THEN REPEAT FOR EACH REDIRECT YOU WANT TO CREATE
}