This would show the user what is the pattern for the date and it will automatically restrict them from submitting invalid data.
It is important to point out that the change event of the DatePicker is triggered when the date from the calendar is changed, rather than on the change of the input. There is an option to attach jQuery event handlers to the Kendo UI widgets, but even on the keypress event, it would be too late to cancel the changes because the value will be already in the input.
Let me know in case additional questions arise.
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