traverseTree Tree

作用

就地遍历树并按顺序执行回调；可写入层级，返回原数组引用。

签名

traverseTree({ tree, callback(node, level), childrenKey='children', levelKey, order='pre' })

引入

import { traverseTree } from 'flit-kit'

参数

参数	类型	默认值	说明
`tree`	`Array<object>`	`[]`	输入树
`callback`	`(node,level)=>void`	必填	回调在原节点上执行
`childrenKey`	`string`	`'children'`	子节点字段名
`levelKey`	`string`	`undefined`	若提供则写入层级到输出节点
`order`	`'pre'	'post'	'level'`

示例

const next = traverseTree({ tree, levelKey: 'level', callback: (node, level) => { node.tag = `L${level}` }, order: 'level' })

说明

先序：当前→子；后序：子→当前；层序：按层走 BFS
函数会就地修改原树节点（写入 level/tag）

复杂度

O(n)

返回值

Array<object> 原数组引用

输出

[
  {
    "id": 1,
    "parentId": null,
    "name": "A",
    "sort": 2,
    "level": 1,
    "tag": "L1",
    "children": [
      {
        "id": 2,
        "parentId": 1,
        "name": "A-1",
        "sort": 1,
        "level": 2,
        "tag": "L2",
        "children": []
      },
      {
        "id": 3,
        "parentId": 1,
        "name": "A-2",
        "sort": 2,
        "level": 2,
        "tag": "L2",
        "children": []
      }
    ]
  }
]