SharePoint Dragons

If you’re planning to use the SharePoint date time control. a good place to start is the followiing: http://karinebosch.wordpress.com/sharepoint-controls/datetimecontrol-control/ It won’t tell you how to use validation controls in combination with it, and there’s an important gotcha involved. If you want to access the textfield rendered by the SharePoint date time control, you need to set the ControlToValidate property to the name of the control in the following format: [control id]$[control id]Date, for example: MyControl$MyControlDate, like so:

<SharePoint:DateTimeControl runat=”server” ID=”MyControl” DateOnly=”true” ShowWeekNumber=”true” LocaleId=”1043″ IsRequiredField=”true” />
<SharePoint:InputFormCustomValidator runat=”server” ID=”MyCustomValidator” ControlToValidate=”MyControl$MyControlDate”
Display=”Dynamic” SetFocusOnError=”true” OnServerValidate=”ValidateFromDateControl” />

Also see: http://www.greggalipeau.com/2008/06/27/sharepoint-datetimecontrol-validation/