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我正在尝试创建自托管System.ServiceModel.Web.WebServiceHost（.NET 4），但是我遇到了构造函数的问题。有三个选项：

  1. WebServiceHost()一个看起来毫无意义的无参数构造函数，因为无法指定服务的类型，甚至无法指定合同。回想起来，它什么也没做——只是一个不调用 base 的空默认构造函数。

  2. WebServiceHost(object singletonInstance, params Uri[] baseAddresses)我不想要一个单例实例，因为这是一个InstanceContextMode.PerCall类。

  3. WebServiceHost(System.Type serviceType, params Uri[] baseAddresses)我想作为服务实例化的类型没有无参数构造函数（这是此方法的要求）。我正在使用 NInject 将参数推送到构造函数中。但是，我试图将其作为自托管测试运行，所以我想避免 DI。

有没有这些方面的选择，或者我不必自我托管？

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1 回答 1

3

要支持没有无参数构造函数的服务类，您需要使用IInstanceProvider知道如何创建服务类的实现。下面的代码显示了一个带有 的代码，您可以在http://blogs.msdn.com/b/carlosfigueira/archive/2011/05/31/wcf-extensibility-iinstanceprovider.aspxWebServiceHost找到有关实例提供程序的更多信息。

public class StackOverflow_9997163
{
    [ServiceContract]
    public class Service
    {
        private int increment;
        public Service(int increment)
        {
            this.increment = increment;
        }
        [WebGet]
        public int Add(int x, int y)
        {
            return x + y + increment;
        }
    }
    class MyInstanceProvider : IInstanceProvider
    {
        Func<Service> serviceCreator;
        public MyInstanceProvider(Func<Service> serviceCreator)
        {
            this.serviceCreator = serviceCreator;
        }

        public object GetInstance(InstanceContext instanceContext, Message message)
        {
            return this.serviceCreator();
        }

        public object GetInstance(InstanceContext instanceContext)
        {
            return this.serviceCreator();
        }

        public void ReleaseInstance(InstanceContext instanceContext, object instance)
        {
        }
    }
    class MyServiceBehavior : IServiceBehavior
    {
        Func<Service> serviceCreator;
        public MyServiceBehavior(Func<Service> serviceCreator)
        {
            this.serviceCreator = serviceCreator;
        }

        public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
        {
        }

        public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
        {
            foreach (ChannelDispatcher cd in serviceHostBase.ChannelDispatchers)
            {
                foreach (EndpointDispatcher ed in cd.Endpoints)
                {
                    ed.DispatchRuntime.InstanceProvider = new MyInstanceProvider(this.serviceCreator);
                }
            }
        }

        public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
        {
        }
    }
    public static void Test()
    {
        string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
        WebServiceHost host = new WebServiceHost(typeof(Service), new Uri(baseAddress));
        int currentIncrement = 1;
        host.Description.Behaviors.Add(new MyServiceBehavior(delegate()
        {
            return new Service(currentIncrement++);
        }));
        host.Open();
        Console.WriteLine("Host opened");

        for (int i = 0; i < 10; i++)
        {
            WebClient c = new WebClient();
            Console.WriteLine(c.DownloadString(baseAddress + "/Add?x=6&y=8"));
        }

        Console.Write("Press ENTER to close the host");
        Console.ReadLine();
        host.Close();
    }
}
于 2012-04-03T16:53:48.403 回答