创建wcf channelfactory<t>

是的,如果你想创建这样的东西-一个静态类来保存所有这些 ChannelFactory<T> 实例-您一定要确保这个类是100%线程安全的,并且在并发访问时不会出错。我还没有使用过.NET 4的很多功能,所以我不能具体评论这些功能——但我绝对建议尽可能安全地使用这些功能。

至于第二个(次要)问题:channelFactory本身是一个静态类,因此不能真正调用 .Close() 方法。如果你想问是否打电话给 关闭() 实际的方法 IChannel 再次强调:是的,尽你最大的努力成为一个好公民,如果你能的话,关闭那些渠道。如果你错过了一个,.net会处理它-但不要只是把你未使用的频道扔到地板上继续-自己清理!-)

下面是一个我用来处理通道工厂的助手类:

public class ChannelFactoryManager : IDisposable
{
    private static Dictionary<Type, ChannelFactory> _factories = new Dictionary<Type,ChannelFactory>();
    private static readonly object _syncRoot = new object();

    public virtual T CreateChannel<T>() where T : class
    {
        return CreateChannel<T>("*", null);
    }

    public virtual T CreateChannel<T>(string endpointConfigurationName) where T : class
    {
        return CreateChannel<T>(endpointConfigurationName, null);
    }

    public virtual T CreateChannel<T>(string endpointConfigurationName, string endpointAddress) where T : class
    {
        T local = GetFactory<T>(endpointConfigurationName, endpointAddress).CreateChannel();
        ((IClientChannel)local).Faulted += ChannelFaulted;
        return local;
    }

    protected virtual ChannelFactory<T> GetFactory<T>(string endpointConfigurationName, string endpointAddress) where T : class
    {
        lock (_syncRoot)
        {
            ChannelFactory factory;
            if (!_factories.TryGetValue(typeof(T), out factory))
            {
                factory = CreateFactoryInstance<T>(endpointConfigurationName, endpointAddress);
                _factories.Add(typeof(T), factory);
            }
            return (factory as ChannelFactory<T>);
        }
    }

    private ChannelFactory CreateFactoryInstance<T>(string endpointConfigurationName, string endpointAddress)
    {
        ChannelFactory factory = null;
        if (!string.IsNullOrEmpty(endpointAddress))
        {
            factory = new ChannelFactory<T>(endpointConfigurationName, new EndpointAddress(endpointAddress));
        }
        else
        {
            factory = new ChannelFactory<T>(endpointConfigurationName);
        }
        factory.Faulted += FactoryFaulted;
        factory.Open();
        return factory;
    }

    private void ChannelFaulted(object sender, EventArgs e)
    {
        IClientChannel channel = (IClientChannel)sender;
        try
        {
            channel.Close();
        }
        catch
        {
            channel.Abort();
        }
        throw new ApplicationException("Exc_ChannelFailure");
    }

    private void FactoryFaulted(object sender, EventArgs args)
    {
        ChannelFactory factory = (ChannelFactory)sender;
        try
        {
            factory.Close();
        }
        catch
        {
            factory.Abort();
        }
        Type[] genericArguments = factory.GetType().GetGenericArguments();
        if ((genericArguments != null) && (genericArguments.Length == 1))
        {
            Type key = genericArguments[0];
            if (_factories.ContainsKey(key))
            {
                _factories.Remove(key);
            }
        }
        throw new ApplicationException("Exc_ChannelFactoryFailure");
    }

    public void Dispose()
    {
        Dispose(true);
    }

    protected virtual void Dispose(bool disposing)
    {
        if (disposing)
        {
            lock (_syncRoot)
            {
                foreach (Type type in _factories.Keys)
                {
                    ChannelFactory factory = _factories[type];
                    try
                    {
                        factory.Close();
                        continue;
                    }
                    catch
                    {
                        factory.Abort();
                        continue;
                    }
                }
                _factories.Clear();
            }
        }
    }
}

然后我定义一个服务调用程序:

public interface IServiceInvoker
{
    R InvokeService<T, R>(Func<T, R> invokeHandler) where T: class;
}

以及一个实现:

public class WCFServiceInvoker : IServiceInvoker
{
    private static ChannelFactoryManager _factoryManager = new ChannelFactoryManager();
    private static ClientSection _clientSection = ConfigurationManager.GetSection("system.serviceModel/client") as ClientSection;

    public R InvokeService<T, R>(Func<T, R> invokeHandler) where T : class
    {
        var endpointNameAddressPair = GetEndpointNameAddressPair(typeof(T));
        T arg = _factoryManager.CreateChannel<T>(endpointNameAddressPair.Key, endpointNameAddressPair.Value);
        ICommunicationObject obj2 = (ICommunicationObject)arg;
        try
        {
            return invokeHandler(arg);
        }
        finally
        {
            try
            {
                if (obj2.State != CommunicationState.Faulted)
                {
                    obj2.Close();
                }
            }
            catch
            {
                obj2.Abort();
            }
        }
    }

    private KeyValuePair<string, string> GetEndpointNameAddressPair(Type serviceContractType)
    {
        var configException = new ConfigurationErrorsException(string.Format("No client endpoint found for type {0}. Please add the section <client><endpoint name=\"myservice\" address=\"http://address/\" binding=\"basicHttpBinding\" contract=\"{0}\"/></client> in the config file.", serviceContractType));
        if (((_clientSection == null) || (_clientSection.Endpoints == null)) || (_clientSection.Endpoints.Count < 1))
        {
            throw configException;
        }
        foreach (ChannelEndpointElement element in _clientSection.Endpoints)
        {
            if (element.Contract == serviceContractType.ToString())
            {
                return new KeyValuePair<string, string>(element.Name, element.Address.AbsoluteUri);
            }
        }
        throw configException;
    }

}

现在,每次需要调用WCF服务时,您都可以使用此功能:

WCFServiceInvoker invoker = new WCFServiceInvoker();
SomeReturnType result = invoker.InvokeService<IMyServiceContract, SomeReturnType>(
    proxy => proxy.SomeMethod()
);

这假定您已经为 IMyServiceContract 配置文件中的服务约定:

<client>
    <endpoint 
        name="myservice" 
        address="http://example.com/" 
        binding="basicHttpBinding" 
        contract="IMyServiceContract" />
</client>

我不喜欢呼叫结构:

WCFServiceInvoker invoker = new WCFServiceInvoker();
var result = invoker.InvokeService<IClaimsService, ICollection<string>>(proxy => proxy.GetStringClaims());

同样,您不能使用同一频道两次。

我已经创建了这个解决方案:

using(var i = Connection<IClaimsService>.Instance)
{           
   var result = i.Channel.GetStringClaims();
}

现在可以重用同一个通道,直到using语句调用Dispose。

getchannel方法基本上是一个channelFactory.createChannel(),我正在使用一些额外的配置。

您可以像其他解决方案一样为ChannelFactory构建一些缓存。

连接类的代码:

public static class Connection<T>
   {
      public static ChannelHolder Instance
      {
         get
         {
            return new ChannelHolder();
         }
      }

      public class ChannelHolder : IDisposable
      {
         public T Channel { get; set; }

         public ChannelHolder()
         {
            this.Channel = GetChannel();
         }

         public void Dispose()
         {
            IChannel connection = null;
            try
            {
               connection = (IChannel)Channel;
               connection.Close();
            }
            catch (Exception)
            {
               if (connection != null)
               {
                  connection.Abort();
               }
            }
         }
      }
}

@Nelsonrothermel,是的,我沿着 未在ChannelFactoryManager ChannelFaulted事件处理程序中使用Try Catch。 所以通道故障会变成

 private void ChannelFaulted(object sender, EventArgs e)
    {
        IClientChannel channel = (IClientChannel)sender;            
        channel.Abort();
    }

似乎允许最初的异常冒泡。 还选择不使用channel.close,因为它似乎引发了异常 因为通道已经处于故障状态。 FactoryFaulted事件处理程序可能有类似的问题。 btw@darin,代码不错…