How do I validate data in Dynamically created TFrame

Does anyone know how to properly validate data which is entered in a
TFrame?  I want to make sure that a user enters data in a particular
way in a TFrame which I am planning to create dynamically.

If you want to know.  This is in a dialog-box with a list of
categories (TListBox) which will dynamically create and destroy frames
as a user switches between categories.

Any ideas are appreciated.  TIA.
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J. Peter Mugaas     E-Mail:  ICQ Number:  14297043
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