When the user enters a value in the DropDownDataWindow or DropDownListBox edit-style column, the value will be checked if it exists in the dropdown list. If exists, the value will be accepted, otherwise, the user will be prompted to enter a different value.
You can enable this validation check by selecting the "Validate value against dropdown choices" option in the painter, or setting the dddw.validation or ddlb.validation property in the script.
This option/property is effective when AllowEdit is enabled.
