Question

我已经通过Visual Studio 2015创建了一个服务引用。通信工作正常，但我必须让应用程序免于app.config文件。我试图创建自己的绑定和端点，但实际上我收到了SystemNullReference。

我的代码示例：

    var binding = CreateBinding();
    var endpoint = new EndpointAddress("http://ws.cdyne.com/emailverify/Emailvernotestemail.asmx");
    var Client = new Testowy.Emailver.EmailVerNoTestEmailSoapClient(binding, endpoint );

private static BasicHttpBinding CreateBinding()
        {
            var binding = new BasicHttpBinding();
            binding.Name = "EmailVerNoTestEmailSoap";
            binding.CloseTimeout = TimeSpan.FromMinutes(1);
            binding.OpenTimeout = TimeSpan.FromMinutes(1);
            binding.ReceiveTimeout = TimeSpan.FromMinutes(10);
            binding.SendTimeout = TimeSpan.FromMinutes(1);
            binding.AllowCookies = false;
            binding.BypassProxyOnLocal = false;
            binding.HostNameComparisonMode = HostNameComparisonMode.StrongWildcard;
            binding.MaxBufferSize = 65536;
            binding.MaxBufferPoolSize = 524288;
            binding.MessageEncoding = WSMessageEncoding.Text;
            binding.TextEncoding = System.Text.Encoding.UTF8;
            binding.TransferMode = TransferMode.Buffered;
            binding.UseDefaultWebProxy = true;

            binding.ReaderQuotas.MaxDepth = 32;
            binding.ReaderQuotas.MaxStringContentLength = 8192;
            binding.ReaderQuotas.MaxArrayLength = 16384;
            binding.ReaderQuotas.MaxBytesPerRead = 4096;
            binding.ReaderQuotas.MaxNameTableCharCount = 16384;

            binding.Security.Mode = BasicHttpSecurityMode.None;
            binding.Security.Transport.ClientCredentialType = HttpClientCredentialType.None;
            binding.Security.Transport.ProxyCredentialType = HttpProxyCredentialType.None;
            binding.Security.Transport.Realm = "";
            binding.Security.Message.ClientCredentialType = BasicHttpMessageCredentialType.UserName;
            binding.Security.Message.AlgorithmSuite = System.ServiceModel.Security.SecurityAlgorithmSuite.Default;
            return binding;
        }

System.NullReferenceException：未将对象引用设置为实例   一个对象。

服务器堆栈跟踪：w   System.ServiceModel.Security.IssuanceTokenProviderBase 1.DoNegotiation(TimeSpan timeout) w System.ServiceModel.Security.SspiNegotiationTokenProvider.OnOpen(TimeSpan timeout) w System.ServiceModel.Security.WrapperSecurityCommunicationObject.OnOpen(TimeSpan timeout) w System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout) w System.ServiceModel.Security.CommunicationObjectSecurityTokenProvider.Open(TimeSpan timeout) w System.ServiceModel.Security.SymmetricSecurityProtocol.OnOpen(TimeSpan timeout) w System.ServiceModel.Security.WrapperSecurityCommunicationObject.OnOpen(TimeSpan timeout) w System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout) w System.ServiceModel.Channels.SecurityChannelFactory {1.ClientSecurityChannel {1}} 1.ClientSecuritySessionChannel.OnOpen（时间跨度   超时）w   System.ServiceModel.Channels.CommunicationObject.Open（时间跨度   超时）w   System.ServiceModel.Channels.ServiceChannel.OnOpen（TimeSpan timeout）
  w System.ServiceModel.Channels.CommunicationObject.Open（TimeSpan   超时）w   System.ServiceModel.Channels.ServiceChannel.CallOpenOnce.System.ServiceModel.Channels.ServiceChannel.ICallOnce.Call（ServiceChannel   频道，TimeSpan超时）w   System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce（时间跨度   超时，CallOnceManager级联）w   System.ServiceModel.Channels.ServiceChannel.EnsureOpened（时间跨度   超时）w System.ServiceModel.Channels.ServiceChannel.Call（String   action，Boolean oneway，ProxyOperationRuntime操作，Object [] ins，   对象[]出局，TimeSpan超时）w   System.ServiceModel.Channels.ServiceChannelProxy.InvokeService（IMethodCallMessage   methodCall，ProxyOperationRuntime operation）w   System.ServiceModel.Channels.ServiceChannelProxy.Invoke（即时聊天   消息）

在[0]处重新抛出异常：w   System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage（即时聊天   reqMsg，IMessage retMsg）w   System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke（MessageData＆安培;   msgData，Int32类型）w   WebServices.Testowy.Emailver.EmailVerNoTestEmailSoap.AdvancedVerifyEmail（字符串   电子邮件，Int32超时，字符串LicenseKey）w   WebServices.Test.GetWebService（）w   C：\ Users \用户michal.warchulinski \源\回购\ Aplixcom_CommonComponents \ Aplixcom_CommonComponents \ Web服务\ ClientClasses.cs：wiersz   65 w App.Main（）w C：\ Users \ michal.warchulinski \ Documents \ Visual   Studio 2015 \ Projects \ Soap \ Soap \ Program.cs：wiersz 22

请原谅我很多文字。什么能提供这个例外的线索？

Answer 1

在调用webservice方法之前，尝试在客户端上调用Open方法。有时它有助于解决一些对象初始化问题。

我们可以根据您的堆栈跟踪看到，它实际上在您调用webservice方法时尝试打开客户端。但显然，与Open方法相比，它尝试以不同的方式打开频道。

不幸的是，我没有足够的知识解释为什么有时需要公开电话，有时不需要。

如果有人能够解释这一点，我会很高兴。

连接到WebService时的SystemNullReference

1 个答案: