event.composedPath()

返回包含当前 EventTarget 作为唯一条目的数组，如果未调度事件则返回空数组。 这在 Node.js 中没有使用，纯粹是为了完整性而提供的。

Returns an array containing the current EventTarget as the only entry or empty if the event is not being dispatched. This is not used in Node.js and is provided purely for completeness.