A construct with a :this element?

Question

In a project I'm currently working on I have a couple of classes, one of this classes contains a constructor which looks like this:

public SomeClass(ISomeInterface someInterface) : this()
{
    /* yada yada */
}

What does the :this mean?

Answer 1

This code assumes that there is also a constructor defined as

public SomeClass(){/* yada yada */}

which will be called before the constructor whose definition you've given.