(PHP 8 >= 8.4.0)
A string representing the classes of the element separated by spaces.
Reflects the element ID through the "id" attribute.
First child element or null.
Last child element or null.
The number of child elements.
The previous sibling element or null.
The next sibling element or null.
注意: 此 DOM 扩展在处理方法或属性时使用 UTF-8 编码。 解析器方法会自动检测编码,或允许调用者指定编码。