无法将 lambda 表达式转换为类型“对象"，因为它不是委托类型 [英] Cannot convert lambda expression to type 'object' because it is not a delegate type

问题描述

我有一个基类，它的 bool 属性如下所示:

I have a base class that has a bool property which looks like this:

public abstract class MyBaseClass
{
     public bool InProgress { get; protected set; }
}

我正在从它继承另一个类并尝试将 InProgress 作为代表添加到字典中.但它给我一个错误.这就是我的派生类的样子:

I am inheriting it another class from it and trying to add InProgress as a delegate to the dictionary. But it throws me an error. This is how my Derived class looks like:

public abstract class MyClass
{
     Dictionary<string, object> dict = new Dictionary<string, object>();
     dict.Add("InProgress", InProgress => base.InProgress = InProgress);

}

这是我得到的错误:

无法将 lambda 表达式转换为类型对象"，因为它不是委托类型

Cannot convert lambda expression to type 'object' because it is not a delegate type

我在这里做错了什么?

推荐答案

最好是强类型的字典，但是如果你先将 lambda 分配给特定的 lambda(委托)，它应该可以工作(因为编译器然后知道委托格式):

Best would be to have the dictionary strongly typed, but if you assign the lambda to a specific lambda (delegate) first, it should work (because the compiler then knows the delegate format):

Action<bool> inp = InProgress => base.InProgress = InProgress;
dict.Add("InProgress", inp);

或者直接施法，效果一样

dict.Add("InProgress", (Action<bool>)(InProgress => base.InProgress = InProgress));

当然，拥有像对象这样的字典格式是可以讨论的，因为您必须知道委托格式才能使用它.

Of course having such a dictionary format as object is discussable, since you'll have to know the delegate format to be able to use it.

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