c# - 在 WCF 服务中时为 "unreachable code detected"

Question

这个问题与THIS QUESTION直接相关但我想因为主题不同，我会为当前问题提出一个新问题。我有一个 WCF 服务、一个服务和一个 GUI。 GUI 将一个 int 传递给 WCF，WCF 应该将其存放到 List<int> IntList 中;然后在服务中我想访问列表。问题是，当我尝试添加到 WCF 服务的列表时，我收到“检测到无法访问的代码”警告，并且当我调试它时，添加行被完全跳过。我怎样才能让这个列表“可达”？

下面是 WCF 代码、对 WCF 的 GUI 调用以及使用 List<> 的服务来自 WCF:

WCF:

[ServiceContract(Namespace = "http://CalcRAService")]
public interface ICalculator
{
    [OperationContract]
    int Add(int n1, int n2);
    [OperationContract]
    List<int> GetAllNumbers();
}

// Implement the ICalculator service contract in a service class.
public class CalculatorService : ICalculator
{
    public List<int> m_myValues = new List<int>();

    // Implement the ICalculator methods.
    public int Add(int n1,int n2)
    {
        int result = n1 + n2;
        return result;
        m_myValues.Add(result);
    }
    public List<int> GetAllNumbers()
    {
        return m_myValues;
    }
}

界面:

private void button1_Click(object sender, EventArgs e)
        {
            using (ChannelFactory<ICalculator> factory = new ChannelFactory<ICalculator>(new NetNamedPipeBinding(), new EndpointAddress("net.pipe://localhost/MyServiceAddress")))
            {
                ICalculator proxy = factory.CreateChannel();                
                int trouble = proxy.Add((int)NUD.Value,(int)NUD.Value);
            }
        }

服务:

protected override void OnStart(string[] args)
{
    if (mHost != null)
    {
        mHost.Close();
    }
    mHost = new ServiceHost(typeof(CalculatorService), new Uri("net.pipe://localhost"));
    mHost.AddServiceEndpoint(typeof(ICalculator), new NetNamedPipeBinding(), "MyServiceAddress");
    mHost.Open();
    using (ChannelFactory<ICalculator> factory = new ChannelFactory<ICalculator>(new NetNamedPipeBinding(), new EndpointAddress("net.pipe://localhost/MyServiceAddress")))
    {
        ICalculator proxy = factory.CreateChannel();
        BigList.AddRange(proxy.GetAllNumbers());
    }
}

Answer 1

所以你有:

int result = n1 + n2;
return result; // <-- Return statement
m_myValues.Add(result); // <-- This code can never be reached!

既然 m_myValues.Add() 不会以任何方式改变 result 的状态，为什么不翻转这些行:

int result = n1 + n2;
m_myValues.Add(result);
return result;