需求：数组转成树状结构

image.png

  1.  data: [{
  2.         label: '张大大',
  3.         children: [
  4.           {
  5.             label: '小亮',
  6.             children: [{ label: '小丽' }, { label: '大光' }]
  7.           }]
  8.       }],

数据：

  1. const arr = [
  2.         { id: '01', name: '张大大', pid: '', job: '项目经理' },
  3.         { id: '02', name: '小亮', pid: '01', job: '产品leader' },
  4.         { id: '03', name: '小美', pid: '01', job: 'UIleader' },
  5.         { id: '04', name: '老马', pid: '01', job: '技术leader' },
  6.         { id: '05', name: '老王', pid: '01', job: '测试leader' },
  7.         { id: '06', name: '老李', pid: '01', job: '运维leader' },
  8.         { id: '07', name: '小丽', pid: '02', job: '产品经理' },
  9.         { id: '08', name: '大光', pid: '02', job: '产品经理' },
  10.         { id: '09', name: '小高', pid: '03', job: 'UI设计师' },
  11.         { id: '10', name: '小刘', pid: '04', job: '前端工程师' },
  12.         { id: '11', name: '小华', pid: '04', job: '后端工程师' },
  13.         { id: '12', name: '小李', pid: '04', job: '后端工程师' },
  14.         { id: '13', name: '小赵', pid: '05', job: '测试工程师' },
  15.         { id: '14', name: '小强', pid: '05', job: '测试工程师' },
  16.         { id: '15', name: '小涛', pid: '06', job: '运维工程师' },
  17.         { id: '16', name: '小才', pid: '07', job: '运维工程师' },
  18.       ]

答案：
方法一

  1. arr.forEach(item => {
  2.         // item.pid 为" "时 返回underfined
  3.         let parent = obj[item.pid]
  4.         if (parent) {
  5.           (parent.children || (parent.children = [])).push(item)
  6.         } else {
  7.           // 这里push的item是pid为undefined的数据
  8.           result.push(item)
  9.         }
  10.       })
  11.       console.log(result)

方法二：用递归函数

  1. function filterArray(data, pid) {
  2.         var tree = []
  3.         var temp
  4.         for (var i = 0; i < data.length; i++) {
  5.           if (data[i].pid == pid) {
  6.             var obj = data[i]
  7.             temp = filterArray(data, data[i].id)
  8.             if (temp.length > 0) {
  9.               obj.children = temp
  10.           }
  11.             tree.push(obj)
  12.         }
  13.       }
  14.         return tree
  15.     }
  16. console.log(filterArray(arr, ''))