namespace web2
{
    class Program
    {
        static void Main(string[] args)
        {
            //creating object of program class to access methods  
            Program obj = new Program();
            //Calling InvokeService method  
            obj.InvokeService();
        }
        public void InvokeService()
        {
            //Calling CreateSOAPWebRequest method  
            HttpWebRequest request = CreateSOAPWebRequest();

            XmlDocument SOAPReqBody = new XmlDocument();
            //SOAP Body Request  
            SOAPReqBody.LoadXml(@"<?xml version=""1.0"" encoding=""utf-8""?>" + 
                                @"<soap:Envelope xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" xmlns:soap=""http://schemas.xmlsoap.org/soap/envelope/"">" +
                                @"<soap:Header>" + 
                                @"<AuthHeader xmlns=""http://tempuri.org/"">" +
                                @"<Username>Username1</Username>" + 
                                @"<Password>Password1</Password>" +
                                @"</AuthHeader>" + 
                                @" </soap:Header>" +
                                @"<soap:Body>" + 
                                @"<HelloWorld xmlns=""http://tempuri.org/""/>" +
                                @"</soap:Body>" + 
                                @"</soap:Envelope>");


            using (Stream stream = request.GetRequestStream())
            {
                SOAPReqBody.Save(stream);
            }
            //Geting response from request  
            using (WebResponse Serviceres = request.GetResponse())
            {
                using (StreamReader rd = new StreamReader(Serviceres.GetResponseStream()))
                {
                    //reading stream  
                    var ServiceResult = rd.ReadToEnd();
                    //writting stream result on console  
                    Console.WriteLine(ServiceResult);
                    Console.ReadLine();
                }
            }
        }

        public HttpWebRequest CreateSOAPWebRequest()
        {
            //Making Web Request  
            HttpWebRequest Req = (HttpWebRequest)WebRequest.Create(@"http://localhost:61711/WebServiceTCW.asmx");
            //SOAPAction  
            Req.Headers.Add(@"SOAPAction:http://tempuri.org/HelloWorld");
            //Content_type  
            Req.ContentType = "text/xml;charset=\"utf-8\"";
            Req.Accept = "text/xml";
            //HTTP method  
            Req.Method = "POST";
            //return HttpWebRequest  
            return Req;
        }
    }
}

namespace WA_TCW
{
    public class AuthHeader : SoapHeader
    {
        public string Username;
        public string Password;
    }

    /// <summary>
    /// Summary description for WebServiceTCW
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line. 
    // [System.Web.Script.Services.ScriptService]
    public class WebServiceTCW : System.Web.Services.WebService
    {
        public AuthHeader Authentication;
        [WebMethod, SoapHeader("Authentication")]
        public string HelloWorld()
        {
            return "Hello World " + 
                Authentication.Username + 
                " " + 
                Authentication.Password;
        }
    }

}