Activator.CreateInstance 和 Ninject 在 asp.net mvc 4 上

Question

我正在尝试在同一个项目中使用反射和 ninject。这是我的代码：

Type type = Type.GetType("MySolution.Project.Web.App_Code.DataClass");
MethodInfo theMethod = type.GetMethod("Events_ListAll");
object classInstance = Activator.CreateInstance(type, null);

这是我的 class，其中包含该方法：

 public class DataClass
    {
        private IEventService eventService;
        public DataClass(IEventService eventService)
        {
            this.eventService = eventService;
        }


        public String Events_ListAll()
        {
            List<Event> lstEvents = eventService.GetEvents().ToList<Event>();
            return "";
        }
    }

我收到一条错误消息，提示未找到构造函数。解决方案是添加一个空的默认构造函数，但这不会注入我想要的 class。有解决办法吗？

Answer 1

你需要一个 IEventService 的具体实例作为参数传递给 DataClass 的 ctor，就像这样 Activator.CreateInstance(type, instance);，所以你有很多方法可以做到这一点，请参阅 2 of :

1st - class 有一个具体的 IEventService

That class where you doing the reflection has a concrete instance of IEventService and then you just pass as param to the Activator:

public class Foo
{
   public Foo(IEventService eventService)
   {
       Type type = Type.GetType("MySolution.Project.Web.App_Code.DataClass");
       MethodInfo theMethod = type.GetMethod("Events_ListAll");
       object classInstance = Activator.CreateInstance(type, eventService);
   }
}

2nd - 获取 Ninject

的 IKernel 实现

If you are using NinjectWebCommom you can just change the bootstrapper prop to public and get the kernel like this NinjectWebCommom.bootstrapper.Kernel.get<IEventService>()

Type type = Type.GetType("MySolution.Project.Web.App_Code.DataClass");
MethodInfo theMethod = type.GetMethod("Events_ListAll");
object classInstance = Activator.CreateInstance(type, Kernel.Get<IEventService>());