Tree 转扁平数据

Tree 数据：

 const treeData = [{
        id: 1,
        label: 'Level one 1',
        type: 1,
        children: [{
          id: 4,
          label: 'Level two 1-1',
          type: 2,
          children: [{
            id: 9,
            label: 'Level three 1-1-1',
            type: 3
          }, {
            id: 10,
            label: 'Level three 1-1-2',
            type: 3
          }]
        }, {
          id: 11,
          label: 'Level three 1-2',
          type: 2,
          children: [{
            id: 12,
            label: 'Level three 1-2-1',
            type: 3
          }, {
            id: 13,
            label: 'Level three 1-2-2',
            type: 3
          }, {
            id: 14,
            label: 'Level three 1-2-3',
            type: 3
          }, {
            id: 15,
            label: 'Level three 1-2-4',
            type: 3
          }]
        }]
      }]

输出结果：

[
  0: {id: 9, label: 'Level three 1-1-1', type: 3}
  1: {id: 10, label: 'Level three 1-1-2', type: 3}
  2: {id: 12, label: 'Level three 1-2-1', type: 3}
  3: {id: 13, label: 'Level three 1-2-2', type: 3}
  4: {id: 14, label: 'Level three 1-2-3', type: 3}
  5: {id: 15, label: 'Level three 1-2-4', type: 3}
]

递归

思路：

1. 声明 res
2. 遍历获取每项子集const { children, ...i } = item
3. 如果 children 存在，使用concant递归连接
4. 不存在则存入 i

 const treeToList = (list) => {
   let res = []
    for(const item of list ){
        const { children, ...i } = item
        if(children && children.length){
           res = res.concat(treeToList(children))
        }else{
           res.push(i)
        }
    }
   return res
 }

使用方法：

 //查看数据是否转换成功
  const treeList = treeToList(treeData)
  console.log('树状结构转扁平结构', treeList)