RadControl, Message Box not working properly
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I want to implement the validation in Add/Edit Appointment Dialog. If i am not entering any data & clicked Ok/ Cancel button, there should be a confirmation message asking whether I want to exit or not. Currently i am doing it in AppointmentEdited command but after popping up the message box but the appointment dialog is closing by itself. How can i prevent this closing and make user stay on that dialog until he cancels or enter the correct info?

Any pointers will be really appreciated.