I am having a problem with mmDropDownList control. The control is bound to a data source and gets its items from another table. if there are no items in the list to choose from then when saving the form, I get the following error: The dataField to which DropDownList is bound to may contain null value.

System.FormatException: Input string was not in a correct format. at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info) at System.String.System.IConvertible.ToInt32(IFormatProvider provider) at System.Convert.ToInt32(Object value) at System.Data.Common.Int32Storage.Set(Int32 record, Object value) at System.Data.DataColumn.set_Item(Int32 record, Object value)Couldn't store <> in Ticket_Contact_id Column. Expected type is Int32.

If DropDownList is populated and I choose one of the valuse then you don't get the error.

This is also true with other controls, for-example if a textbox is bound to a DateTime Field then upon saving if the data field was null and a date is not typed in the textbox, you get the same error.

Does anyone know what's the best way to get round this issue.

Thanks,

Ilyas