using SOAP service in c#

client app

consuming soap service , console application 

using System;
using System.IO;
using System.Net;
using System.Xml;

namespace UsingSOAPRequest
{
    class Program
    {
        static void Main(string[] args)
        {
            //creating object of program class to access methods 
            Program obj = new Program();
            Console.WriteLine("Please Enter Input values..");
            //Reading input values from console 
            int a = Convert.ToInt32(Console.ReadLine());
            int b = Convert.ToInt32(Console.ReadLine());
            //Calling InvokeService method 
            obj.InvokeService(a, b);
        }
        public void InvokeService(int a, int b)
        {
            //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:soap=""http://schemas.xmlsoap.org/soap/envelope/"" xmlns:xsi=""http://www.w3.org/2001/XMLSchema-   instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema""> 
             <soap:Body> 
                <Addition xmlns=""http://tempuri.org/""> 
                  <a>" + a + @"</a> 
                  <b>" + b + @"</b> 
                </Addition> 
              </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:52168/Service.asmx");
            //SOAPAction 
            Req.Headers.Add(@"SOAPAction:http://tempuri.org/subtract");
            //Content_type 
            Req.ContentType = "text/xml;charset=\"utf-8\"";
            Req.Accept = "text/xml";
            //HTTP method 
            Req.Method = "POST";
            //return HttpWebRequest 
            return Req;
        }
    }
}

server side 
dot net 3.5  web site -> asp.net web service 

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.Services;

[WebService(Namespace = "http://tempuri.org/")]

[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]

// 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 Service : System.Web.Services.WebService

{

    public Service () {

        //Uncomment the following line if using designed components 

        //InitializeComponent(); 

    }

    [WebMethod]

    public string HelloWorld() {

        return "Hello World";

    }

    [WebMethod]

    

    public string sum(int a, int b)

    {

        return (a + b).ToString();

    }

    [WebMethod]

    public int subtract(int a, int b)

    {

        return a - b;

    }

    [WebMethod]

    public int multiply(int a, int b)

    {

        return a * b;

    }

    [WebMethod]

    public int divide(int a, int b)

    {

        return a / b;

    }

}