1 | root | One Form.Item: the label, the control and the messages under it. layout puts the label beside or above the control. |
2 | label | The item's label, with the required mark from rules or required. Paired with the control when the item has a name. |
3 | content | The column holding your control, the item's children. |
4 | help | The block under the control that shows validation messages, or your own help. |
5 | helpItem | One message in the help block. A field with several failing rules shows one per rule. |
6 | extra | The lasting hint under the messages, from extra. It stays when the error goes away. |