vue拖拽功能

              
              
                  {{item.column}}
              



              数值：
              
                  {{item.column}}
              


goback(val, type) {
      if (type === 'measure') {
        if (val.type === 'column') {
          this.dragFrom.measures.push(val)
          this.dragTo.values.forEach((item, index) => {
            if (item.alias === val.alias) {
              this.dragTo.values.splice(index, 1)
            }
          })
        }
      }
},
drag: function(event,index,val) {
      if(val==='1'){
        event.dataTransfer.setData('Text', index);
      }
      const data = {
        isVal:val?val:'',
        type: event.target.className,
        value: event.target.innerText.replace(/(^\s*)|(\s*$)/g, '')
      }
      this.dragData = data
},
 drop: function(event) {
      if (event.target.innerText.indexOf('数值') !== -1) {
        if (this.dragData.isVal==='1') {
          let arr = this.dragTo.values.concat([])
          let dragIndex = event.dataTransfer.getData('Text');
          let temp = arr.splice(dragIndex, 1);
          arr.splice(arr.length, 0, temp[0]);//一直加到最后面
          this.dragTo.values = arr;
          console.log(this.dragTo.values)
        } else {
          this.dragFrom.measures.forEach((item, index) => {
            if (item.alias === this.dragData.value) {
              this.dragTo.values.push(item)
              this.dragFrom.measures.splice(index, 1)
            }
          })
        }
      }
      event.preventDefault()
},
allowDrop: function(event) {
      event.preventDefault()
},
dragLeave(event) {
      event.preventDefault()
},
dragEnter(event) {
      event.preventDefault()
},