C#动态调用webService出现 基础连接已经关闭: 未能为 SSL/TLS 安全通道建立信任关系。

在远程调用WebService时出现下面的情况：

              

这种情况一般是由于证书有问题时出现，如果在浏览器中打开是这种情况：

           

解决方法新建一个类，代码如下：

    public static class CertificateTrust
    {
 
        public static void SetCertificatePolicy()
        {
            ServicePointManager.ServerCertificateValidationCallback
                       += RemoteCertificateValidate;
        }  
        private static bool RemoteCertificateValidate(
           object sender, X509Certificate cert,
            X509Chain chain, SslPolicyErrors error)
        {
            
            System.Console.WriteLine("Warning, trust any certificate");
            return true;
        }
    } 

在动态编译WebService的代码中调用上面的类就可以了，注意调用的位置，一定要在打开前调用，下面代码的红色部分

动态编译WebSerivce的代码如下：

    public class WSHelper
    {
        /// < summary>           
        /// 动态调用web服务         
        /// < /summary>          
        /// < param name="url">WSDL服务地址< /param> 
        /// < param name="methodname">方法名< /param>           
        /// < param name="args">参数< /param>           
        /// < returns>< /returns>          
        public static object InvokeWebService(string url, string methodname, object[] args)
        {
            return WSHelper.InvokeWebService(url, null, methodname, args);
        }
        /// < summary>          
        /// 动态调用web服务 
        /// < /summary>          
        /// < param name="url">WSDL服务地址< /param>
        /// < param name="classname">类名< /param>  
        /// < param name="methodname">方法名< /param>  
        /// < param name="args">参数< /param> 
        /// < returns>< /returns>
        public static object InvokeWebService(string url, string classname, string methodname, object[] args)
        {
            string @namespace = "EnterpriseServerBase.WebService.DynamicWebCalling";
            if ((classname == null) || (classname == ""))
            {
                classname = WSHelper.GetWsClassName(url);
            }
            try
            {   //获取WSDL   
                WebClient wc = new WebClient();

                CertificateTrust.SetCertificatePolicy();//证书出现问题时调用此代码

                Stream stream = wc.OpenRead(url + "?WSDL");
                ServiceDescription sd = ServiceDescription.Read(stream);
                ServiceDescriptionImporter sdi = new ServiceDescriptionImporter();
                sdi.AddServiceDescription(sd, "", "");
                CodeNamespace cn = new CodeNamespace(@namespace);
                //生成客户端代理类代码          
                CodeCompileUnit ccu = new CodeCompileUnit();
                ccu.Namespaces.Add(cn);
                sdi.Import(cn, ccu);
                CSharpCodeProvider icc = new CSharpCodeProvider();
                //设定编译参数添加所需要的DLL文件                 
                CompilerParameters cplist = new CompilerParameters();
                cplist.GenerateExecutable = false;
                cplist.GenerateInMemory = true;
                cplist.ReferencedAssemblies.Add("System.dll");
                cplist.ReferencedAssemblies.Add("System.XML.dll");
                cplist.ReferencedAssemblies.Add("System.Web.Services.dll");
                cplist.ReferencedAssemblies.Add("System.Data.dll");
                //编译代理类                 
                CompilerResults cr = icc.CompileAssemblyFromDom(cplist, ccu);
                if (true == cr.Errors.HasErrors)
                {
                    System.Text.StringBuilder sb = new System.Text.StringBuilder();
                    foreach (System.CodeDom.Compiler.CompilerError ce in cr.Errors)
                    {
                        sb.Append(ce.ToString());
                        sb.Append(System.Environment.NewLine);
                    }
                    throw new Exception(sb.ToString());
                }
                //生成代理实例，并调用方法   
                System.Reflection.Assembly assembly = cr.CompiledAssembly;
                Type t = assembly.GetType(@namespace + "." + classname, true, true);
                object obj = Activator.CreateInstance(t);
                System.Reflection.MethodInfo mi = t.GetMethod(methodname);
                return mi.Invoke(obj, args); 
            }
            catch (Exception ex)
            {
                throw new Exception(ex.InnerException.Message, new Exception(ex.InnerException.StackTrace));
            }
        }
        private static string GetWsClassName(string wsUrl)
        {
            string[] parts = wsUrl.Split('/');
            string[] pps = parts[parts.Length - 1].Split('.');
            return pps[0];
        }
    }

调用动态编译的代码如下：

                string url = "http://localhost:81/WebServiceLogin.asmx";
                string[] args = new string[2];
                args[0] = "参数1";
                args[1] = "参数2";
                object result = WSHelper.InvokeWebService(url, "HelloWorld", args);