From Base Form property

Note:  This property is available only for components on extended forms, that is forms created as extensions of other forms.

This property specifies whether the value of the component is to be taken from the base form or treated as an extended form component.

When set to True, this property indicates that the value of the component is to be taken from the base form. In this case, when the component is selected in Design Mode:

  • The component itself displays a lock icon, indicating that the component is locked from editing.
  • Most of the component properties on the property sheet are "grayed out", indicating that they cannot be modified.

When set to False, this property indicates that the component is to be treated as if it were native to the extended form. In this case, you can modify the component in Design Mode the same as any other extended form component.