“Action<object?, EventArgs>”和“EventHandler(object?sender, EventArgs e)”有什么区别？

Question

public delegate void Action<object?, EventArgs>(object? sender, EventArgs e);

public delegate void EventHandler(object? sender, EventArgs e);

这两行有什么区别？它们在功能上似乎是相同的。

Answer 1

事实上，没有什么区别：

EventHandler a;
Action<object?, EventArgs> b;

void c(object? o, EventArgs e) { }

void d() {
    a = c; b = c; // no error
}