>I don't know but maybe, "MyBase" keyword is to make it synchronize with the "Me" keyword. Isn't it right to say that it has the same functionality with DODEFAULT() of VFP?

First, I don't know VB, so...

MyBase sounds more like a reference to the parent class (super class). DODEFAULT executes the method with
the same name as the currently executed one, but from the parent class. There's no reference to the parent class
in DODEFAULT and it cannot be used to call a method with a different name. (BTW, calling a different method from
the parent class is always bad design!!!)

Vlad