委派一个动作<裁判的T1，T2和GT; [英] Delegate for an Action< ref T1, T2>

问题描述

我试图创造，这需要裁判参数的静态方法的委托。请不要问我为什么做这样的事情繁琐。它是学习如何.NET，C＃和反思工作，以及如何优化它的一部分

I'm trying to create a delegate of a static method which takes a ref argument. Please don't ask why I'm doing such a cockamamie thing. It's all part of learning how .Net, C#, and reflection work and how to optimize it.

我的代码是：

    public struct DataRow
    {

        private double t;
        static public void Cram_T(ref DataRow dr, double a_t)
        {
            dr.t = a_t;
        }
    }
 ''''
  Type myType = typeof(DataRow);
  MethodInfo my_Cram_T_Method = myType.GetMethod("Cram_T");
  var myCram_T_Delegate = 
         Delegate.CreateDelegate(typeof(Action<DataRow, Double>),      
                                 my_Cram_T_Method) 
                                 as Action<DataRow, Double>;

这给了我一个绑定错误，因为（我认为）通用的动作不匹配方法。

This gives me a binding error because (I think) the generic action doesn't match the method.

在监视窗口中检查Cram_T_Method的值给出

Inspecting the value of Cram_T_Method in the watch window gives

{Void Cram_T(DataRow ByRef, Double)}

然后我使用ref关键字在行动尝试：

I then tried using the ref keyword in the Action:

  var myCram_T_Delegate = 
         Delegate.CreateDelegate(typeof(Action<ref DataRow, Double>),         
                                 my_Cram_T_Method) 
                                 as Action<ref DataRow, Double>;

但是，这不会编译。 C＃编译器电抗器在令牌REF。

But this won't compile. The C# compiler chokes at the token "ref".

什么是创建委托的正确方法？

What is the right way to create this delegate?

推荐答案

创建自己的委托类型：

delegate void MyAction(ref DataRow dataRow, double doubleValue);

和使用 MyAction 在<$的C $ C>动作<裁判的DataRow，双方式> - 这，正如您所指出的那样，不编译

And use MyAction in place of Action<ref DataRow, Double> -- which, as you've noted, doesn't compile.

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