首先：HTML中，关键点是监听拖拽的三个阶段，即：dragstart/dragover/dragend，注意：要拖拽元素必须加上draggable="true"

<ul @dragstart="onDragStart"    @dragover="onDragOver"    @dragend="onDragEnd"    ref="taskListUl">  <li v-for="(subTask,index) in subTaskList"      draggable="true"      :id="subTask.id"      :key="subTask.id">    <el-row>      <el-col :lg="20">        <div  class="main">          <el-row>            <el-col :span="3"><el-checkbox></el-checkbox></el-col>            <el-col :span="21" class="taskEdit" v-if="show.isShowEdit !== index" :title="subTask.name">{{subTask.name}}</el-col>            <el-col :span="21" v-else>              <el-row style="width: 300px;">                <el-form ref="taskEditForm" :model="subTask">                  <el-col :span="14">                    <el-input v-model="subTask.name" size="mini"                              @keyup.enter.native="saveSubTask('subTaskForm',subTask);showEditTitle()"></el-input>                  </el-col>                  <el-col :span="10">                    <el-button type="primary" style="font-size:12px;color:#fff;margin-left:4px;padding:5px 8px;border:0;"                               size="mini" @click="saveSubTask('subTaskForm',subTask);handleTaskEdit()">保存</el-button>                    <el-button style="font-size:12px;padding:5px 8px;border:0;" size="mini" @click="handleTaskEdit">取消</el-button>                  </el-col>                </el-form>              </el-row>            </el-col>          </el-row>        </div>        <div class="icon1" v-if="show.isShowEdit !== index">          <el-button circle size="mini" @click="handleTaskEdit(index)"><i class="el-icon-edit"></i></el-button>          <el-button circle size="mini" @click="handleTaskDelete(index,subTask.id)"><i class="el-icon-delete"></i></el-button>        </div>        <div class="icon2">          <el-button circle size="mini"><i class="el-icon-s-finance"></i></el-button>          <el-button circle size="mini"><i class="el-icon-user"></i></el-button>        </div>      </el-col>    </el-row>  </li></ul>其次，JavaScript中data() {  return {  　　subTaskList: []

　　}},methods: {

onDragStart(event){     //用于在拖拽开始时获取被拖拽元素  console.log("drag start")  this.draging=event.target;  console.log(this.draging);},onDragOver(event){    //用于在拖拽过程中，获取拖拽元素经过的对象，以及对元素顺序做出调整  console.log('drag move');  this.target=event.path[5];    //li的位置  let targetTop=event.target.getBoundingClientRect().top;  let dragingTop=this.draging.getBoundingClientRect().top;  if (this.target.nodeName === "LI"&&this.target !== this.draging) {    if (this.target) {      if (this.target.animated) {        return;      }    }    if(this._index(this.draging)<this._index(this.target)){      this.target.parentNode.insertBefore(this.draging,this.target.nextSibling);    }else{      this.target.parentNode.insertBefore(this.draging, this.target);    }    this._anim(targetTop,this.target);    this._anim(dragingTop,this.draging);  }},_anim(startPos,dom) {    //用于重绘元素  let offset = startPos - dom.getBoundingClientRect().top;  dom.style.transition = "none";  dom.style.transform = `translateY(${offset}px)`;  //触发重绘  dom.offsetWidth;  dom.style.transition="transform .3s";  dom.style.transform=``;  clearTimeout(dom.animated);  dom.animated=setTimeout(()=>{    dom.style.transition="";    dom.style.transform=``;    dom.animated=false;  },300)},onDragEnd(event){   //结束后跟俊最终拖拽调整subTaskList数组

  console.log('drag end');  //获取排序后的li节点数组  let currentNodes=Array.from(this.$refs.taskListUl.childNodes);  let newArr = [];  for(let i=0;i<currentNodes.length;i++) {    for(let j=0;j<this.subTaskList.length;j++) {      if(currentNodes[i].id == this.subTaskList[j].id){        newArr[i] = this.subTaskList[j];      }    }  }  this.subTaskList = newArr;  console.log(this.subTaskList);},

_index(el){    //用于根据元素id来获取对应元素的索引值

  let domData=Array.from(this.$refs.taskListUl.childNodes);  return domData.findIndex((currentValue,index,arr)=>{    return el.id == currentValue.id;  });},

}