To achieve the desired, you could hide the end date picker by handling the OnClientFormCreated
event of the RadScheduler. Note that even if it will be not visible, you will have to update accordingly the selected value
in the End DatePicker every time the date in the Start Picker changes.
At the end you will have both dates set, but the user will choose only the start one. This is needed because each appointment requires both Start and End dates to be specified.
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