classList
dom.classList.contains('black')
// 删除 black
dom.classList.remove('black')
// 新增.red
dom.classList.add('red')
className
let cName = elementNodeReference.className;
elementNodeReference.className = cName;
classList
dom.classList.contains('black')
// 删除 black
dom.classList.remove('black')
// 新增.red
dom.classList.add('red')
className
let cName = elementNodeReference.className;
elementNodeReference.className = cName;