react.js组件实现拖拽复制和可排序的示例代码

// 当一个元素或是选中的文字被拖拽释放到一个有效的释放目标位置时
 drop(dropedSort, data, sortKey, dropedUid, codeKey, ee) {
  ee.preventDefault();
  const code = ee.dataTransfer.getData("code");
  const uId = ee.dataTransfer.getData("uId");
  const dragedItem = ee.dataTransfer.getData("item");
  const sort = ee.dataTransfer.getData("sort");
  if (uId === dropedUid) {
   if (sort < dropedSort) {
    data.map(item => {
     if (item[codeKey] === code) {
      item[sortKey] = dropedSort;
     } else if (item[sortKey] > sort && item[sortKey] < dropedSort + 1) {
      item[sortKey]--;
     }
     return item;
    });
   } else {
    data.map(item => {
     if (item[codeKey] === code) {
      item[sortKey] = dropedSort;
     } else if (item[sortKey] > dropedSort - 1 && item[sortKey] < sort) {
      item[sortKey]++;
     }
     return item;
    });
   }
  } else if (this.props.isAcceptAdd) {
   let objDragedItem = JSON.parse(dragedItem);
   if (data.filter(item => item[codeKey] === objDragedItem[codeKey]).length === 0) {
    const maxSort = Math.max.apply(Math, data.map(citem => citem[sortKey]));
    data.map(item => {
     if (dropedSort === maxSort) {
      objDragedItem[sortKey] = dropedSort + 1;
     } else {
      if (item.sort > dropedSort) {
       objDragedItem[sortKey] = dropedSort + 1;
       item[sortKey]++
      }
     }
     return item
    });
    data.push(objDragedItem)
   }
  }
  this.props.onChange(data)
  if (ee.target.className.indexOf('droppingContent') !== -1) {
   ee.target.className = styles.droppedcontent;
  }
 }