如何在 c# 中为不同的类传递函数指针委托

Question

在 C++ 中， 对于一个接收返回类型为 void 的函数指针的函数，例如：

void TakesFun(Func<void ()>  fun ){
    fun();
}

上面的函数可以通过这些方式调用

//if foo is a function returning void but is declared in global space and not part of another class
TakesFun(bind(foo));   
//if foo is a function returning void but is declared in class called ClassX and the function is required to be called for object "obj".
TakesFun(bind(ClassX::foo, obj));   
//if foo is a function taking an integer as argument and returning void but is declared in class called ClassX and the function is required to be called for object "obj".
TakesFun(bind(ClassX::foo, obj, 5)); //5 is the argument supplied to function foo   

您能帮我为 3 个类似的函数调用编写 C# 代码吗？我尝试阅读 Delegates，但示例并未涵盖上述所有 3 种情况。

Answer 1

正如@Backs 所说，您可以像这样定义TakesFun 函数：

void TakesFun(Action action) => action();

如果需要传参数，可以这样：

void TakesFun<TParam>(Action<TParam> action, TParam p) => action(p);

您的 3 个示例将是：

TakesFun(SomeClass.Foo); // 'Foo' is a static function of 'SomeClass' class
TakesFun(obj.Foo); // 'Foo' is a function of some class and obj is instance of this class
TakesFun(obj.Foo, "parameter"); // as above, but will pass string as parameter to 'Foo'

Answer 2

您可以随时传递Action：

void TakesFun(Action action)
{
    action();
}
///...
TestFun(() => SomeMethod(1,2,3));