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我是 Ninject 的新手。它在调用常规依赖类时效果很好。

但是，我无法在自定义反射中调用依赖项。

我也尝试过构造函数注入。它抛出异常 -No parameterless constructor defined for this object.

我怎样才能实现它？如果有更好的技术，我愿意改变我的设计。

谢谢！

这里是入口点

请注意以下代码仅用于演示 -

var squareCalculation = Activator.CreateInstance(
    Type.GetType("SquareCalculation")) as ICalculation;
int square = squareCalculation.Calculate(1);

var multiplyByTwoCalculation = Activator.CreateInstance(
    Type.GetType("MultiplyByTwoCalculation"))  as ICalculation;
int multiply = multiplyByTwoCalculation.Calculate(2);

计算

public interface ICalculation
{
    int Calculate(int number);
}

public class SquareCalculation : ICalculation
{
    // SquareService is not injecting.
    [Inject]
    public ISquareService SquareService { get; set; }

    public int Calculate(int number)
    {
        // *** This is the method I would like to call. It is unique. ****
        SquareService.Monday(1);

        return number * number;
    }
}

public class MultiplyByTwoCalculation : ICalculation
{
    // MultiplyByTwoService is not injecting.
    [Inject]
    public IMultiplyByTwoService MultiplyByTwoService { get; set; }

    public int Calculate(int number)
    {
        // *** This is the method I would like to call. It is unique. ****
        MultiplyByTwoService.Tuesday(1, 2, "a");

        return number * 2;
    }
}

Ninject App_Start

这只是我通过 NuGet 下载的默认设置。

[assembly: WebActivator.PreApplicationStartMethod(typeof(MyApp.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(MyApp.App_Start.NinjectWebCommon), "Stop")]

namespace MyApp.App_Start
{
    using System;
    using System.Web;

    using Microsoft.Web.Infrastructure.DynamicModuleHelper;

    using Ninject;
    using Ninject.Web.Common;

    public static class NinjectWebCommon 
    {
        .....

        /// <summary>
        /// Load your modules or register your services here!
        /// </summary>
        /// <param name="kernel">The kernel.</param>
        private static void RegisterServices(IKernel kernel)
        {
            kernel.Bind<ISquareService>().To<SquareService>().InSingletonScope();
            kernel.Bind<IMultiplyByTwoService>().To<MultiplyByTwoService>().InSingletonScope();
        }        
    }
}
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1 回答 1

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通过使用Activator.CreateInstance()您绕过 Ninject，就像您在使用new运算符时所做的那样。因此，您有责任完全创建它们或调用kernel.Inject(theNewlyCreatedObject)自己。

一般来说，Activator.CreateInstance直接使用是个坏主意。最好实现一个 Ninject Provider，在里面放上你的自定义代码，然后Bind使用那种类型的类ToProvider()

于 2013-11-04T21:05:27.233 回答