XML - 需要使用循环添加更多子节点

<field name="dob_day" type="list" default="select"
            description="COM_USERS_REGISTER_DOB_DAY_DESC"
            filter="string"
            label="COM_USERS_REGISTER_DOB_DAY_LABEL"
            message="COM_USERS_REGISTER_DOB_DAY_MESSAGE"
            required="true"
            >
            <option value="select">Day</option>
            <option value="1">1</option>
                    .......
                    .......
        </field>
<field name="dob_day" type="list" default="sele