1.参考连接:https://docs.microsoft.com/zh-cn/dotnet/api/system.web.services.protocols.soaphttpclientprotocol?view=netframework-4.7.2

2.webservice

namespace WS
    /// <summary>
    /// WebService1 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    //[SoapDocumentService(RoutingStyle = SoapServiceRoutingStyle.RequestElement)]
    // 若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消注释以下行。 
    // [System.Web.Script.Services.ScriptService]
    public class WebService1 : System.Web.Services.WebService
        [WebMethod]
        public string HelloWorld()
            return "Hello World";
        [WebMethod]
        public string Sum(int a, int b,out int c) {
            Stream sm = Context.Request.InputStream;
            StreamReader sr = new StreamReader(sm, System.Text.Encoding.UTF8);
            string requestXml = sr.ReadToEnd();
            c = 3;
            return $"{a}+{b}={a + b}"+requestXml;
        [WebMethod]
        public string Sum1(int a)
            return a.ToString();
        [WebMethod]
        public Result Test(string step,Test e) {
            return new Result {
                A = e.A,
                B = e.B,
                C=e.A+e.B
    public class Test {
        public string A { get; set; }
        public string B { get; set; }
    public class Result
        public string A { get; set; }
        public string B { get; set; }
        public string C { get; set; }
　　注意：方法和参数，需要wz一致。
namespace ConsoleApp3
    [WebServiceBinding(Namespace = "http://tempuri.org/")]
    public class SoapTest : SoapHttpClientProtocol
        public SoapTest()
            Url = "http://localhost:58271/WebService1.asmx";
        [SoapDocumentMethod]
        public Result Test(string step, Test e)
            var a = Invoke("Test", new object[] { step, e })[0] as Result;
            return a;
        [SoapDocumentMethod]
        public string Sum1(int a)
            var b = Invoke("Sum1", new object[] { a })[0] as string;
            return b;
    public class Test {
        public string A { get; set; }
        public string B { get; set; }
    public class Result {
        public string A { get; set; }
        public string B { get; set; }
        public string C { get; set; }
4.方法调用
static void Main(string[] args)
            string _url = "http://localhost:58271/WebService1.asmx";
            var soap = new SoapTest();
            var b = soap.Sum1(1);
            var a = soap.Test("1",new Test { A="1",B="2"});