Question

我有一个使用Unity的项目，我正在尝试实现.NET Remoting。我有一个NET Remoting Server，用于现有的服务层，它具有使用Enterpise Library数据访问应用程序块的数据层。问题是由于Remoting在调用TestService时需要无参数构造函数获取空引用异常。关于如何用Unity实现这个的任何想法？

这是我的代码：

服务层的TestService：

public class TestService : MarshalByRefObject, ITestService
{
    private ITestRepository repository;

    public TestService(ITestRepository repository)
    {
        this.repository = repository;        
    }

    public TestService() <--- parameterless constructor
    {}

    public List<Book> GetBooks()
    {
        return repository.GetBooks();
    }

数据层的TestRepository：

public class TestRepository : ITestRepository
{
    private Database db;

    public TestRepository(Database db)
    {
        this.db = db;      
    }

    public List<Book> GetBooks()
    {
      List<Book> list = new List<Book>();
        list.Add(new Book(1, "test book 1"));
        list.Add(new Book(2, "test book 2"));
        return list;
    }

图书课程：

[Serializable]
public class Book : MarshalByRefObject
{
    public int ID { get; set; }
    public string Name { get; set; }

    public Book() { }
    public Book(int id, string name)
    {
        this.ID = id;
        this.Name = name;
    }
}

简单测试RemotingServer：

TestRepository testRepository;
TestService testService;

IUnityContainer container = new UnityContainer();

container.AddNewExtension<EnterpriseLibraryCoreExtension>();
container.AddNewExtension<DataAccessBlockExtension>();


container.RegisterType<ITestRepository, TestRepository>();

container.RegisterType<ITestService, TestService>();

testService = container.Resolve<TestService>();

TcpServerChannel channel = new TcpServerChannel(9988);
ChannelServices.RegisterChannel(channel);
RemotingConfiguration.RegisterWellKnownServiceType(typeof(TestService), "TestService", WellKnownObjectMode.SingleCall);
System.Console.WriteLine("Press Any Key");
System.Console.ReadKey();

Simple Remoting客户端：

ChannelServices.RegisterChannel(new TcpClientChannel());
            ITestService testService = (ITestService)Activator.GetObject(typeof(ITestService), "tcp://localhost:9988/TestService");


        foreach(Book item in testService.GetBooks())
        {
            Console.WriteLine("Book:\n" + item.Name);    
        }


        Console.ReadKey();

以下是完整的例外情况：

第40行正在调用repository.GetBooks（）;

在TestService.cs中的Test.Services.IssueService.GetBooks（）：第40行在System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage（IntPtr md，Object [] args，Object server，Int32 methodPtr，Boolean fExecuteInContext，Object []＆amp; outArgs）在System.Runtime.Remoting.Messaging.StackBuilderSink.PrivateProcessMessage（RuntimeMethodHandle md，Object [] args，Object server，Int32 methodPtr，Boolean fExecuteInContext，Object []＆amp; outArgs）在System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage（IMessage msg，Int32 methodPtr，Boolean fExecuteInContext）

谢谢，

约翰

.NET Remoting with Service，它使用带有Unity的DAAB，提供空引用异常

0 个答案: