>If there someone I don't trust, it's a developper :)
>
>Seriously, I would like to develop my control as a black box. It's throwing an error now if an illegal value is assigned (ERROR nErrorNo), so that the developper will notice that he screwed up :) But that work only if he assign a value programatically, not from the property sheet.
>
>I may check the property in the control, but I wanted to avoid this by not accepting invalid values in the first place.
>


The only way to do this is with a builder.