获取某个js块的实时高度

使用的是window的MutationObserver这个api。

const DOMWatcher = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver

this.DOMWatcher =new DOMWatcher(() => {

// 监测到DOM变化，重新计算高度

  let height = getComputedStyle(this.$refs.leftContent).getPropertyValue('height')

this.$refs.rightHeight.style.height = height

this.leftHeight = height

})

this.DOMWatcher.observe(this.$refs.leftContent, {

childList:true,

  attributes:true,

  characterData:true,

  subtree:true

})