ServiceContract中层次结构中的通用接口

本文关键字：接口 层次结构 ServiceContract | 更新日期: 2023-09-27 18:22:10

我有一个通用接口：

[ServiceContract]
public interface IGenericDataRepository<T> where T : class
{
    [OperationContract]
    IList<T> GetAll(params Expression<Func<T, object>>[] navigationProperties);
    [OperationContract]
    IList<T> GetList(Func<T, bool> where, params Expression<Func<T, object>>[] navigationProperties);
    [OperationContract]
    T GetSingle(Func<T, bool> where, params Expression<Func<T, object>>[] navigationProperties);
    [OperationContract]
    void Add(params T[] items);
    [OperationContract]
    void Update(params T[] items);
    [OperationContract]
    void Remove(params T[] items);
}

应该在WCF服务中使用，如下所示：

[ServiceContract]
public interface ICustomerService : IGenericDataRepository<Customer>
{
    [OperationContract]
    Customer GetCustomers();
}

该服务通过以下代码行公开：

Uri baseHttpAddress = new Uri("http://localhost:9999/CustomerService");
ServiceHost customerServiceHost = new ServiceHost(typeof(CustomerService), baseHttpAddress);
customerServiceHost.AddServiceEndpoint(typeof(ICustomerService), new WSHttpBinding(), "");
 ServiceMetadataBehavior serviceMetadataBehavior = new ServiceMetadataBehavior { HttpGetEnabled = true };
 ServiceDebugBehavior serviceDebugBehavior = new ServiceDebugBehavior { IncludeExceptionDetailInFaults = true};    customerServiceHost.Description.Behaviors.Add(serviceMetadataBehavior);
  customerServiceHost.Open();

然而，这似乎并不奏效。在ServiceConrtacts的层次结构中不可能有一个通用接口吗？我找不到关于它的一些信息。

问题是，当我想将服务添加为服务引用时，我无法连接到该服务——通过使用WCF TestClient，我得到了以下异常：

Error: Cannot obtain Metadata from http://localhost:9999/CustomerService If this is a Windows (R) Communication Foundation service to which you have access, please check that you have enabled metadata publishing at the specified address.  For help enabling metadata publishing, please refer to the MSDN documentation at http://go.microsoft.com/fwlink/?LinkId=65455.WS-Metadata Exchange Error    URI: http://localhost:9999/CustomerService    Metadata contains a reference that cannot be resolved: 'http://localhost:9999/CustomerService'.    <?xml version="1.0" encoding="utf-16"?><Fault xmlns="http://www.w3.org/2003/05/soap-envelope"><Code><Value>Sender</Value><Subcode><Value xmlns:a="http://schemas.xmlsoap.org/ws/2005/02/sc">a:BadContextToken</Value></Subcode></Code><Reason><Text xml:lang="de-DE">The message could not be processed. This is most likely because the action 'http://schemas.xmlsoap.org/ws/2004/09/transfer/Get' is incorrect or because the message contains an invalid or expired security context token or because there is a mismatch between bindings. The security context token would be invalid if the service aborted the channel due to inactivity. To prevent the service from aborting idle sessions prematurely increase the Receive timeout on the service endpoint's binding.</Text></Reason></Fault>HTTP GET Error    URI: http://localhost:9999/CustomerService    There was an error downloading 'http://localhost:9999/CustomerService'.    The request failed with the error message:--<HTML><HEAD><STYLE type="text/css">#content{ FONT-SIZE: 0.7em; PADDING-BOTTOM: 2em; MARGIN-LEFT: 30px}BODY{MARGIN-TOP: 0px; MARGIN-LEFT: 0px; COLOR: #000000; FONT-FAMILY: Verdana; BACKGROUND-COLOR: white}P{MARGIN-TOP: 0px; MARGIN-BOTTOM: 12px; COLOR: #000000; FONT-FAMILY: Verdana}PRE{BORDER-RIGHT: #f0f0e0 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #f0f0e0 1px solid; MARGIN-TOP: -5px; PADDING-LEFT: 5px; FONT-SIZE: 1.2em; PADDING-BOTTOM: 5px; BORDER-LEFT: #f0f0e0 1px solid; PADDING-TOP: 5px; BORDER-BOTTOM: #f0f0e0 1px solid; FONT-FAMILY: Courier New; BACKGROUND-COLOR: #e5e5cc}.heading1{MARGIN-TOP: 0px; PADDING-LEFT: 15px; FONT-WEIGHT: normal; FONT-SIZE: 26px; MARGIN-BOTTOM: 0px; PADDING-BOTTOM: 3px; MARGIN-LEFT: -30px; WIDTH: 100%; COLOR: #ffffff; PADDING-TOP: 10px; FONT-FAMILY: Tahoma; BACKGROUND-COLOR: #003366}.intro{MARGIN-LEFT: -15px}</STYLE><TITLE>Service</TITLE></HEAD><BODY><DIV id="content"><P class="heading1">Service</P><BR/><P class="intro">The server was unable to process the request due to an internal error.  For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the <serviceDebug> configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework SDK documentation and inspect the server trace logs.</P></DIV></BODY></HTML>--.

非常感谢！

ServiceContract中层次结构中的通用接口

您不能真正将泛型与WCF一起使用。主要原因是WCF用于交换消息。

现在，您可以使用已知类型的基本对象，而不是T.

您也不能通过服务传递函数指针，因为它们不能序列化。记住，序列化的经验法则是实现必须是具体的。

[DataContract]
[KnownType(typeOf(Customer)]
public abstract class GenericType
{
}
[DataContract]
public class Customer : GenericType
{
}

现在我会重新考虑你的设计。请记住，WCF是一项服务，您需要这样对待它。在我看来，你的界面就像是可以直接与数据存储对话的东西。你可能需要在它前面一层。

错误

"元数据包含无法解析的引用"

根子句是System.Linq.Expressions.Expression类不可序列化。如果删除那些具有Func和Expression参数的方法，将起作用。

您必须实现自己的查询类或使用wcf数据服务

相关文章：