I have a form with a couple of TWebDBEdits, a TWebDBLookupComboBox and a TWebDBDateTimePicker. All linked to a TWebDatasource.
When the value is changed by the user the TWebDBEdit and TWebDBLookupComboBox fire the TWebDatasource.OnDataChanged event, however the TWebDBDateTimePicker does not.
Also, while TWebDBEdit and TWebDBLookupComboBox updates the dataset when the control exits, the TWebDBDateTimePicker does not (which is why the TWebDatasource.OnDataChanged doesn't fire I guess).