C#: TextBox Validation = hh:mm AM|PM

Hi,

I need help in validating my textbox in Windows Application: Windows Form using C#.

startTimeTextBox and endTimeTextBox should only accept values hh:mm AM|PM (e.g. 09:00 AM or 9:00 AM) and to check it before leaving the said textbox but I can't seem to make it work like that.

Hope someone can help me do it.

Thanks,

MukuroRokudo