Verificar se arquivo existe atraves de URL

private bool existeArquivo(string url)
    {
        try
        {
            return (WebRequest.Create(url).GetResponse().GetResponseStream().CanRead);



            /*
            HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
            //Setting the Request method HEAD, you can also use GET too.
            request.Method = HEAD;
            //Getting the Web Response.
            HttpWebResponse response = request.GetResponse() as HttpWebResponse;
            //Returns TURE if the Status code == 200
            return (response.StatusCode == HttpStatusCode.OK);
             */
        }
        catch
        {
            return false;
        }  
    }