The Format event occurs when the DateTimePicker is requesting text to be displayed in a callback field.
[Visual Basic] Overridable Protected Sub OnFormat( _ ByVal dtfevent As DateTimeFormatEventArgs _ ) [C#] protected virtual void OnFormat( DateTimeFormatEventArgs dtfevent ); [C++] protected: virtual void OnFormat( DateTimeFormatEventArgs* dtfevent ); [JScript] protected function OnFormat( dtfevent : DateTimeFormatEventArgs );
DateTimePicker Class | DateTimePicker Members | System.WinForms Namespace | AddOnFormat | RemoveOnFormat | cor.comctl.DateTimeFormatEventArgs