Thanks for your help David and sorry if I am so late to respond. I am not sure I understand well what your suggesting me to do . I am quite starting to learn VFP .
1) Is mcControlSource an added property in the class ?
2) Is the code that you sent me in the class definition , and if yes then I suppose all of it is the different methods ?
3) Now . When I create a form with a field that uses that class , do I need to do something special as far as properties of methods is concerned in the form's properties sheet ?

Thanks again ,

Pierre Sauve

P.S. Sorry for the syntax errors in my text . I am French Canadian and I do not know english perfectly .