webService报错由于连接方在一段时间后没有正确答复或连接的主机没有反应，连接尝试失败

public static object InvokeWebService(string url, string className, string methodName, object[] args)

        {

            string _namespace = "EnterpriseServerBase.WebService.DynamicWebCalling";

            if (string.IsNullOrEmpty(className))

            {

                className = GetWsClassName(url);

            }



            try

            {

                //获取wsdl

                WebClient wc = new WebClient();

                string _url = url.Trim();

                if (!_url.Contains("?wsdl"))

                {

                    _url += "?wsdl";

                }



                Stream stream = wc.OpenRead(_url);



                ServiceDescription sd = ServiceDescription.Read(stream);

                ServiceDescriptionImporter sdi = new ServiceDescriptionImporter();

                sdi.AddServiceDescription(sd, "", "");



                //生成客户端代理类

                CodeNamespace cn = new CodeNamespace(_namespace);

                CodeCompileUnit ccu = new CodeCompileUnit();

                ccu.Namespaces.Add(cn);

                sdi.Import(cn, ccu);

                CSharpCodeProvider csc = new CSharpCodeProvider();

                ICodeCompiler icc = csc.CreateCompiler();



                //设定编译参数

                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 (cr.Errors.HasErrors)

                {

                    StringBuilder sb = new StringBuilder();

                    foreach (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

                Assembly assembly = cr.CompiledAssembly;

                Type t = assembly.GetType(_namespace + "." + className, true, true);

                object obj = Activator.CreateInstance(t);



                MethodInfo info = t.GetMethod(methodName);

                if (info == null)

                {

                    throw new Exception("未在接口 [" + className + "] 中找到方法 [" + methodName + "]");

                }

                object result = info.Invoke(obj, args);



                return result;

            }

            catch

            {

                throw;

            }

        }