NamedNodeMap.getNamedItem()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015年7月.
NamedNodeMap 接口的 NamedNodeMap.getNamedItem() 方法返回对应给定名称的属性，如果没有对应名称的属性则返回 null