Thanks a lot .

>>I gonna picking up some old c++ book and study delphi to
>>make the concept of oop more clearly .
>
>Why not try for the VFP version? One old book that may be useful still for concepts (though the code is a little out of date) is:
>
>"The Revolutionary Guide to Visual FoxPro OOP"
>Phelps et al
>Wrox Press, May 1996