See How can I make my form Modal/Modeless on the fly. FAQ #7921

>How can i change the windowtype property in execution mode from 0 to
>1. I need to make a modal form in execution mode not in dising mode. I was trying doing this:
>
>do form form1
> form1.windowtype=1
>
>but dont work because i need to change the property before de form1 execute.