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我正在尝试将来自 WCF 服务的双工回调接收到我的 Web api 操作中。但不知何故，这是行不通的。我无法在 web api 中获得回调。

如果我使用控制台应用程序而不是 asp.net 核心应用程序，那么控制台应用程序会收到回调。因此，WCF 服务设置正确并且工作正常。不知何故，问题出在 web api 控制器中（特别与回调处理程序有关）

请建议我应该如何在 web api 中编写回调处理程序？

这些是我到目前为止尝试过的步骤-

Step1：使用 netTcpBinding 创建 WCF 服务

namespace WcfServiceLibrary1
{
    [ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)]
    public class CalculatorService : ICalculatorDuplex
    {
        double result;
        string equation;
        ICalculatorDuplexCallback callback = null;

        public CalculatorService()
        {
            result = 0.0D;
            equation = result.ToString();
            callback = OperationContext.Current.GetCallbackChannel<ICalculatorDuplexCallback>();
        }

        public void Clear()
        {
            callback.Equation(equation + " = " + result.ToString());
            result = 0.0D;
            equation = result.ToString();
            System.IO.File.AppendAllText(@"D:\Sanket\wcf_test.txt", DateTime.Now.ToShortTimeString() + "\t" + equation + "\t" + result + Environment.NewLine);
        }

        public void AddTo(double n)
        {
            result += n;
            equation += " + " + n.ToString();
            callback.Equals(result);
        }

        public void SubtractFrom(double n)
        {
            result -= n;
            equation += " - " + n.ToString();
            callback.Equals(result);
        }

        public void MultiplyBy(double n)
        {
            result *= n;
            equation += " * " + n.ToString();
            callback.Equals(result);
        }

        public void DivideBy(double n)
        {
            result /= n;
            equation += " / " + n.ToString();
            callback.Equals(result);
        }

    }

Step2：使用WCF Connected Service扩展将服务参考代码生成到本文提到的名为reference.cs的文件中

第3 步：为了创建工具生成的 WCF 客户端类型的实例并与您的 Web 服务通信，我在我的 Web api 控制器中编写了以下代码 -

    [Produces("application/json")]
    [Route("api/[controller]")]
    public class WcfServiceTestingController : Controller
    {
        CalculatorDuplexClient wcfClient
            = new CalculatorDuplexClient(CalculatorDuplexClientBase.EndpointConfiguration.NetTcpBinding_ICalculatorDuplex);

        // GET: api/values
        [HttpGet]
        public ActionResult Get()
        {

            try
            {
                // Call the AddTo service operation.
                double value = 100.00D;
                wcfClient.AddToAsync(value);

                // Call the SubtractFrom service operation.
                value = 50.00D;
                wcfClient.SubtractFromAsync(value);

                // Call the MultiplyBy service operation.
                value = 17.65D;
                wcfClient.MultiplyByAsync(value);

                // Call the DivideBy service operation.
                value = 2.00D;
                wcfClient.DivideByAsync(value);

                // Complete equation.
                wcfClient.ClearAsync();

                // Wait for callback messages to complete before
                // closing.
                System.Threading.Thread.Sleep(5000);

                // Close the WCF client.
                wcfClient.Close();
                Console.WriteLine("Done!");
                return Json("Done!");
            }
            catch (TimeoutException timeProblem)
            {
                Console.WriteLine("The service operation timed out. " + timeProblem.Message);
                wcfClient.Abort();
                Console.Read();
                return Json("TimeoutException");
            }
            catch (CommunicationException commProblem)
            {
                Console.WriteLine("There was a communication problem. " + commProblem.Message);
                wcfClient.Abort();
                Console.Read();
                return Json("CommunicationException");
            }



        }

        private class CallbackHandler : ICalculatorDuplexCallback
        {
            public CallbackHandler()
            {
                Console.WriteLine("CallbackHandler");
            }

            public void Equals(double result)
            {
                Console.WriteLine(" Result({0})", result);
            }

            public void Equation(string eqn)
            {
                Console.WriteLine(" Equation({0})", eqn);
            }
        }
    }
}

我的环境：

Visual Studio 2015 Update3 + WCF 连接服务扩展

带有 netTcpBinding 的 WCF 服务

ASP.NET 核心 1.0 应用程序

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0 回答 0