WCF send custom header request - dirty way

gistfile1.txt

string url = "http://url.com/*.wsdl";
using (var client = new WebClient())
{
    var data = System.IO.File.ReadAllText(HostingEnvironment.MapPath(@"~/App_Data/request.xml"));
    client.Headers.Add("Content-Type", "text/xml;charset=utf-8");

    client.Encoding = Encoding.GetEncoding("ISO-8859-1");
    client.Credentials = new NetworkCredential("username", "pass");

    client.Headers.Add("SOAPAction", "\"http://url.com/wsdl?action\"");
    var response = client.UploadString("http://url.com/wsdl", data);
}