vue实现可拖拽div大小的方法

dragDiv(allBox, leftBox, resizeBox, rightBox, leftMin = 200, rightMin = 200) {
         var box = document.getElementsByClassName(allBox);
         var left = document.getElementsByClassName(leftBox);
         var resize = document.getElementsByClassName(resizeBox);
         var right = document.getElementsByClassName(rightBox);
         for(let i = 0; i < resize.length; i++) {
            // 鼠标按下事件
            resize[i].onmousedown = function(e) {
               // 颜色改变提醒
               resize[i].style.background = '#818181';
               var startX = e.clientX;
               resize[i].left = resize[i].offsetLeft;
               // 鼠标拖动事件
               document.onmousemove = function(e) {
                  var endX = e.clientX;
                  var moveLen = resize[i].left + (endX - startX); // （endx-startx）=移动的距离。resize[i].left+移动的距离=左边区域最后的宽度
                  var maxT = box[i].clientWidth - resize[i].offsetWidth; // 容器宽度 - 左边区域的宽度 = 右边区域的宽度
                  if(moveLen < leftMin) moveLen = leftMin;
                  if(moveLen > maxT - rightMin) moveLen = maxT - rightMin;
                  resize[i].style.left = moveLen; // 设置左侧区域的宽度
                  for(let j = 0; j < left.length; j++) {
                     left[j].style.width = moveLen + 'px';
                     right[j].style.width = (box[i].clientWidth - moveLen - 10) + 'px';
                  }
               };
               // 鼠标松开事件
               document.onmouseup = function(evt) {
                  // 颜色恢复
                  resize[i].style.background = '#d6d6d6';
                  document.onmousemove = null;
                  document.onmouseup = null;
                  resize[i].releaseCapture && resize[i].releaseCapture(); // 当你不在需要继续获得鼠标消息就要应该调用ReleaseCapture()释放掉
               resize[i].setCapture && resize[i].setCapture(); // 该函数在属于当前线程的指定窗口里设置鼠标捕获
               return false;
            };
         }
      },

<template>
  <div class="container" id="content_box">
    <div class="tab">左侧Tab</div>
    <div class="menu" ref="menu">
      左侧菜单
      <div class="menu-resize" ref="menuResize"></div>
    </div>
    <div class="content">
      中心区域
      <div class="opera" ref="opera">
        <div class="opera-resize" ref="operaResize"></div>
        操作区域
      </div>
  </div>
</template>
<script>
export default {
  name: "dropWidth",
  mounted() {
    this.$nextTick(() => {
      this.dropSize();
    })
  },
  methods: {
    dropSize() {
      let that = this,
          menuWidth = 200,
          operaHeight = 200;
      this.$refs.menuResize.onmousedown = function () {
        document.onmousemove = function (e) {
          let clientX = e.clientX;
          // 最大宽度
          if(clientX>=330){
            clientX = 330;
          }
          // 最小宽度
          if(clientX<=230){
            clientX = 230;
          // TODO 这里减的是最左侧tab的宽度
          menuWidth = clientX - 30;
          that.$refs.menu.style.width = clientX - 30 +"px";
        }
        document.onmouseup = function () {
          console.log('当前宽度', menuWidth);
          document.onmousemove = null;
          document.onmouseup = null;
          that.releaseCapture && that.releaseCapture()
      }
      this.$refs.operaResize.onmousedown = function () {
          let clientY = e.clientY;
          console.log(clientY)
          if(clientY<=100){
            clientY = 100;
          if(clientY>=300){
            clientY = 300;
          operaHeight = clientY;
          // TODO 这里需要取反向
          that.$refs.opera.style.height = 400 - clientY +"px";
          console.log('当前宽度', operaHeight);
    }
  }
}
</script>
<style scoped>
.container {
  width: 1000px;
  height: 400px;
  border: 2px solid #dddddd;
  display: flex;
  justify-content: center;
.tab {
  width: 30px;
  height: 100%;
  background-color: #EC8C32;
  flex-shrink: 0;
  flex-grow: 0;
.menu {
  width: 200px;
  background-color: #AAB6E0;
  position: relative;
.content {
  width: 100%;
.opera {
  height: 200px;
  position: absolute;
  bottom: 0;
  background-color: #F2BE25;
.menu-resize {
  width: 5px;
  top: 0;
  right: 0;
  cursor: col-resize;
.opera-resize {
  height: 5px;
  left: 0;
  cursor: row-resize;
</style>