WCF透明代理类，动态调用，支持async/await

我们希望WCF客户端调用采用透明代理方式，不用添加服务引用，也不用Invoke的方式，通过ChannelFactory<>动态产生通道，实现服务接口进行调用，并且支持async/await，当然也不用在Config中配置serviceModel。

服务端代码：

[ServiceContract]
public interface IGameService
{
    [OperationContract]
    Task DoWorkAsync(string arg);

    [OperationContract]
    void DoWork(string arg);
}

public class GameService : IGameService
{
    public async Task<string> DoWorkAsync(string arg)
    {
        return await Task.FromResult($"Hello {arg}, I am the GameService.");
    }
    public string DoWork(string arg)
    {
        return $"Hello {arg}, I am the GameService.";
    }
}

[ServiceContract]
public interface IPlayerService
{
    [OperationContract]
    Task<string> DoWorkAsync(string arg);

    [OperationContract]
    string DoWork(string arg);
}

public class PlayerService : IPlayerService
{
    public async Task<string> DoWorkAsync(string arg)
    {
        return await Task.FromResult($"Hello {arg}, I am the PlayerService.");
    }
    public async string DoWork(string arg)
    {
        return $"Hello {arg}, I am the PlayerService.";
    }
}

代理类

动态创建服务对象，ChannelFactory<T>的运用，一个抽象类

namespace Wettery.Infrastructure.Wcf
{
    public enum WcfBindingType
    {
        BasicHttpBinding,
        NetNamedPipeBinding,
        NetPeerTcpBinding,
        NetTcpBinding,
        WebHttpBinding,
        WSDualHttpBinding,
        WSFederationHttpBinding,
        WSHttpBinding
    }

    public abstract class WcfChannelClient<TChannel> : IDisposable
    {
        public abstract string ServiceUrl { get; }

        private Binding _binding;
        public virtual Binding Binding
        {
            get
            {
                if (_binding == null)
                    _binding = CreateBinding(WcfBindingType.NetTcpBinding);

                return _binding;
            }
        }

        protected TChannel _channel;
        public TChannel Channel
        {
            get { return _channel; }
        }
        protected IClientChannel ClientChannel
        {
            get { return (IClientChannel)_channel; }
        }

        public WcfChannelClient()
        {
            if (string.IsNullOrEmpty(this.ServiceUrl)) throw new NotSupportedException("ServiceUrl is not overridden by derived classes.");
            var chanFactory = new ChannelFactory<TChannel>(this.Binding, this.ServiceUrl);
            _channel = chanFactory.CreateChannel();
            this.ClientChannel.Open();
        }

        protected virtual void Dispose(bool disposing)
        {
            if (disposing && this.ClientChannel != null)
            {
                try
                {
                    this.ClientChannel.Close(TimeSpan.FromSeconds(2));
                }
                catch
                {
                    this.ClientChannel.Abort();
                }
            }

            //TODO: free unmanaged resources
        }
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
        ~WcfChannelClient()
        {
            Dispose(false);
        }

        private static Binding CreateBinding(WcfBindingType binding)
        {
            Binding bindinginstance = null;
            if (binding == WcfBindingType.BasicHttpBinding)
            {
                BasicHttpBinding ws = new BasicHttpBinding();
                ws.MaxBufferSize = 2147483647;
                ws.MaxBufferPoolSize = 2147483647;
                ws.MaxReceivedMessageSize = 2147483647;
                ws.ReaderQuotas.MaxStringContentLength = 2147483647;
                ws.CloseTimeout = new TimeSpan(0, 10, 0);
                ws.OpenTimeout = new TimeSpan(0, 10, 0);
                ws.ReceiveTimeout = new TimeSpan(0, 10, 0);
                ws.SendTimeout = new TimeSpan(0, 10, 0);
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.NetNamedPipeBinding)
            {
                NetNamedPipeBinding ws = new NetNamedPipeBinding();
                ws.MaxReceivedMessageSize = 65535000;
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.NetPeerTcpBinding)
            {
                //NetPeerTcpBinding ws = new NetPeerTcpBinding();
                //ws.MaxReceivedMessageSize = 65535000;
                //bindinginstance = ws;
                throw new NotImplementedException();
            }
            else if (binding == WcfBindingType.NetTcpBinding)
            {
                NetTcpBinding ws = new NetTcpBinding();
                ws.MaxReceivedMessageSize = 65535000;
                ws.Security.Mode = SecurityMode.None;
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.WebHttpBinding)
            {
                WebHttpBinding ws = new WebHttpBinding(); //Restful style
                ws.MaxReceivedMessageSize = 65535000;
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.WSDualHttpBinding)
            {
                WSDualHttpBinding ws = new WSDualHttpBinding();
                ws.MaxReceivedMessageSize = 65535000;
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.WSFederationHttpBinding)
            {
                WSFederationHttpBinding ws = new WSFederationHttpBinding();
                ws.MaxReceivedMessageSize = 65535000;
                bindinginstance = ws;
            }
            else if (binding == WcfBindingType.WSHttpBinding)
            {
                WSHttpBinding ws = new WSHttpBinding(SecurityMode.None);
                ws.MaxReceivedMessageSize = 65535000;
                ws.Security.Message.ClientCredentialType = MessageCredentialType.Windows;
                ws.Security.Transport.ClientCredentialType = HttpClientCredentialType.Windows;
                bindinginstance = ws;
            }
            return bindinginstance;

        }        
    }
}

针对每个WCF服务派生一个代理类，在其中重写ServiceUrl与Binding，ServiceUrl可以配置到Config中，Binding不重写默认采用NetTcpBinding

public class GameServiceClient : WcfChannelClient<IGameService>
    {
        public override string ServiceUrl
        {
            get
            {
                return "net.tcp://localhost:21336/GameService.svc";
            }
        }
    }

public class PlayerServiceClient : WcfChannelClient<IPlayerService>
    {
        public override string ServiceUrl
        {
            get
            {
                return "net.tcp://localhost:21336/PlayerService.svc";
            }
        }
    }

客户端调用

using (var client = new GameServiceClient())
{
    client.Channel.DoWork("thinkpig");  //无返回值
    await client.Channel.DoWorkAsync("thinkpig");  //无返回值异步
}

using (var client = new PlayerServiceClient())
{
    var result = client.Channel.DoWork("thinkdog");  //有返回值
    result = await client.Channel.DoWorkAsync("thinkdog");  //有返回值异步
}

关于WCF寄宿主机可以参考前两篇文章

WCF绑定netTcpBinding寄宿到控制台应用程序

WCF绑定netTcpBinding寄宿到IIS