I have a function of this sort
void func(params object[] parameters) {
//Function Body
}
It can accept parameters of the following sort
func(10, "hello", 30.0);
func(10,20);
and so on.
I wanted to create an Action delegate for the above function. Is it possible? If not then why?
You can't use the existing Action delegates with params, but you can declare your own delegate that way:
public delegate void ParamsAction(params object[] arguments)
Then:
// Note that this doesn't have to have params, but it can do
public void Foo(object[] args)
{
// Whatever
}
...
ParamsAction action = Foo;
action("a", 10, 20, "b");
Of course you can create an Action<object[]> for your existing method - but you lose the params aspect of it, as that's not declared in Action<T>. So for example:
public static void Foo(params object[] x)
{
}
...
Action<object[]> func = Foo;
func("a", 10, 20, "b"); // Invalid
func(new object[] { "a", 10, 20, "b" }); // Valid
So if you're calling the delegate from code which wants to use params, you need a delegate type which includes that in the declaration (as per the first part). If you just want to create a delegate which accepts an object[], then you can create an instance of Action<object[]> using a method which has params in its signature - it's just a modifier, effectively.
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