function() : this(null) {}

Question

Can someone please explain the following syntactic sugar?

protected MyConstructor() : this(null)

Mainly I am interested in this part: ": this(null)"

I know how protected, constructors and "this" keyword work, but am confused and cannot find any detailed information of the last part all put-together in all my online searches.

Edit: I should add that it is in a public abstract class. So I guess the constructor is calling the implementers constructor.

Thanks

Answer 1

It calls another class constructor that has a parameter:

protected MyConstructor() : this(null) { }  // This calls the other constructor

protected MyConstructor(object whatever)
{
    Frob(whatever);
}