Element：childElementCount 属性
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Element.childElementCount 只读属性返回该元素的子元素数量。
示例
js
let sidebar = document.getElementById("sidebar");
if (sidebar.childElementCount > 0) {
// 做点什么
}
规范
| Specification |
|---|
| DOM # dom-parentnode-childelementcount |