C# Passing an Optional Function to another Function

Question

I know that in C# you can pass a function as a parameter to another function with something that looks like this:

public bool DoSomething(int param1, int param2 = 0, Func<bool, bool> f) 
{
//Do Some work
//Run function f
bool i = f(true);
return true;
}

I also know that if you initialize one of the parameters, in my example, the second parameter (int param2 = 0), then the parameter is optional.

How can I make the third parameter (the function f) as an optional parameter? What should I initialize it to?

I would appreciate some help!

What you ask for is called a "Delegate". One of the many things they had to invent to replace naked pointers. I am unsure if Delegates can be combiend with optiuonal parameters, however. — Christopher
– Christopher, Commented Nov 12, 2018 at 17:16
Initialize it to a Func<bool, bool>? i.e., (something) => !something — Heretic Monkey
– Heretic Monkey, Commented Nov 12, 2018 at 17:16

Dmitry Stepanov · Accepted Answer · 2018-11-12 17:16:15Z

3

public bool DoSomething(int param1, int param2 = 0, Func<bool, bool> f = null) 
{
 ...
}

answered Nov 12, 2018 at 17:16

Dmitry Stepanov

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