ASP.NET核心反射迪

Question

我做了RabbitMQ的設置，例如我的分機：

public static class QueueExtension 
{ 
    public static IServiceCollection UseQueue<TQueue, TApiService>(this IServiceCollection services, string host, string login, 
     string password, string queue, IDictionary<string, object> arg) where TQueue : class, IEventHandler where TApiService : class, IService 
    { 
     if (services == null) 
      throw new ArgumentNullException("services"); 
     return UseQueue<TQueue, TApiService>(services, typeof(TQueue), typeof(TApiService), host, login, password, queue, arg); 
    } 

    public static IServiceCollection UseQueue<T, Y>(this IServiceCollection services, Type queueType, Type apiServiceType, string host, string login, 
     string password, string queue, IDictionary<string, object> arg) where T : IEventHandler where Y: IService 
    { 
     if (services == null) 
      throw new ArgumentNullException("services"); 
     if (queueType == null) 
      throw new ArgumentNullException("queueType"); 
     if (apiServiceType == null) 
      throw new ArgumentNullException("apiServiceType"); 

     var parametersQueueType = queueType 
      .GetConstructors() 
      .SelectMany(p=>p.GetParameters()) 
      .Select(p=>p.ParameterType) 
      .ToList(); 

     var parametersType = services 
      .Where(p => parametersQueueType.Select(z => z.FullName) 
      .Contains(p.ServiceType.FullName)) 
      .ToList(); 

     var parameters = new List<object>(); 

     parametersType.ForEach(p => 
     { 
      parameters.Add((Y)Activator.CreateInstance(p.ImplementationType)); 
     }); 

     var impl = (T)Activator.CreateInstance(queueType, parameters); 

     var queueService = new QueueServiceImpl(host, login, password, queue, arg); 
     queueService.ReceivedMessage += (sender, ea) => 
     { 
      var body = ea.Body; 
      var message = Encoding.UTF8.GetString(body); 
      impl.MessageHandler(message); 
     }; 
     queueService.Start(); 

     return services; 
    } 

} 

我用它在startup.cs：

services.UseQueue<PrimaryEventHandlerImpl, IRsmService(
    Configuration[AppConstants.HostPrimary], 
    Configuration[AppConstants.LoginPrimary], 
    Configuration[AppConstants.PasswordPrimary], 
    Configuration[AppConstants.QueuePrimary], 
    arg 
); 

但它錯在所有的時間做錯誤在這行：

var impl = (T)Activator.CreateInstance(queueType, parameters); 

都說：

未找到構造函數Monq.Core.Service.RSMModeGenerator.Services.PrimaryEventHandlerImpl。

但我PrimaryEventHandlerImpl.cs：

public class PrimaryEventHandlerImpl : IEventHandler 
{ 
    private IRsmService _rsmService; 

    public PrimaryEventHandlerImpl() 
    { 

    } 
    public PrimaryEventHandlerImpl(IRsmService rsmService) 
    { 
     _rsmService = rsmService; 
    } 
    public void MessageHandler(string json) 
    { 
     var events = JsonExtensions.JsonToObject<Event>(json); 
     if (events.Priority != 5) 
     { 
      //var services = _rsmService.GetServices(); 

     } 
    } 
} 

我想這樣做使它正常工作？

Answer 1

變化

var impl = (T)Activator.CreateInstance(queueType, parameters); 

到

var impl = (T)Activator.CreateInstance(queueType, parameters.ToArray()); 

Answer 2

什麼你企圖做解決了很多簡單和靈活的方式。

static IServiceCollection UseQueue<T>(this IServiceCollection services, 
             RabbitMQOptions options) 
     where T : class, IEventHandler 
    { 
     if (services == null) 
      throw new ArgumentNullException("services"); 
     if (options == null) 
      throw new ArgumentNullException("options"); 

     services.AddTransient<T>(); 
     services.AddTransient<IQueueService, QueueServiceImpl>(); 
     services.AddSingleton<RabbitMQOptions>(sp => { return options; }); 

     var serviceProvider = services.BuildServiceProvider(); 

     var rabbitImpl = serviceProvider.GetService<T>(); 
     var queueService = serviceProvider.GetService<IQueueService>(); 

     queueService.ReceivedMessage += async (sender, ea) => 
     { 
      var body = ea.Body; 
      var message = Encoding.UTF8.GetString(body); 
      await rabbitImpl.MessageHandler(message); 
      queueService.Channel.BasicAck(ea.DeliveryTag, false); 
     }; 
     queueService.Start(); 

     return services; 
    }