想问一下从后端得到如下所示数据，怎么转换为el-menu的三级菜单的数据结构（面试时遇到的笔试题没写出来）(语言-javascript)

Question

后端传入的数据

list = [
  {"ID": 1,"MenuOne": "教学楼","MenuTwo": "A01教室","NoteName": "A01前"},
  {"ID": 2,"MenuOne": "教学楼","MenuTwo": "A01教室","NoteName": "A01后"},
  {"ID": 3,"MenuOne": "教学楼","MenuTwo": "A02教室","NoteName": "A02前"},
  {"ID": 4,"MenuOne": "教学楼","MenuTwo": "A02教室","NoteName": "A02后"},
  {"ID": 5,"MenuOne": "操场","MenuTwo": "跑道","NoteName": "跑道前"},
  {"ID": 6,"MenuOne": "操场","MenuTwo": "跑道","NoteName": "跑道后"},
  {"ID": 7,"MenuOne": "操场","MenuTwo": "厕所","NoteName": "厕所前"},
  {"ID": 8,"MenuOne": "操场","MenuTwo": "厕所","NoteName": "厕所后"},
  {"ID": 9,"MenuOne": "食堂","MenuTwo": "","NoteName": "食堂前"},
  {"ID": 10,"MenuOne": "食堂","MenuTwo": "","NoteName": "食堂后"},
  {"ID": 11,"MenuOne": "食堂","MenuTwo": "","NoteName": "食堂左"},
  {"ID": 12,"MenuOne": "食堂","MenuTwo": "","NoteName": "食堂右"},
]

我想要达到的结果

menu = [
  {
    id:'1',
    label:'教学楼',
    child:[
      {
        label:'A01教室',
        child:[
          {id:'1-1',label:'A01前'},
          {id:'1-2',label:'A01后'}
        ]
      },
      {
        label:'A02教室',
        child:[
          {id:'1-3',label:'A02前'},
          {id:'1-4',label:'A02后'}
        ]
      },
    ]
  },
  {
    id:'2',
    label:'操场',
    child:[
      {
        label:'跑道',
        child:[
          {id:'2-1',label:'跑道前'},
          {id:'2-2',label:'跑道后'}
        ]
      },
      {
        label:'厕所',
        child:[
          {id:'2-3',label:'厕所前'},
          {id:'2-4',label:'厕所后'}
        ]
      },
    ]
  },
  {
    id:'3',
    label:'食堂',
    child:[
      {
        label:'',
        child:[
          {id:'3-1',label:'食堂前'},
          {id:'3-2',label:'食堂后'},
          {id:'3-3',label:'食堂左'},
          {id:'3-4',label:'食堂右'}
        ]
      }
    ]
  }
]

Answer 1

var list = [
        { ID: 1, MenuOne: "教学楼", MenuTwo: "A01教室", NoteName: "A01前" },
        { ID: 2, MenuOne: "教学楼", MenuTwo: "A01教室", NoteName: "A01后" },
        { ID: 3, MenuOne: "教学楼", MenuTwo: "A02教室", NoteName: "A02前" },
        { ID: 4, MenuOne: "教学楼", MenuTwo: "A02教室", NoteName: "A02后" },
        { ID: 5, MenuOne: "操场", MenuTwo: "跑道", NoteName: "跑道前" },
        { ID: 6, MenuOne: "操场", MenuTwo: "跑道", NoteName: "跑道后" },
        { ID: 7, MenuOne: "操场", MenuTwo: "厕所", NoteName: "厕所前" },
        { ID: 8, MenuOne: "操场", MenuTwo: "厕所", NoteName: "厕所后" },
        { ID: 9, MenuOne: "食堂", MenuTwo: "", NoteName: "食堂前" },
        { ID: 10, MenuOne: "食堂", MenuTwo: "", NoteName: "食堂后" },
        { ID: 11, MenuOne: "食堂", MenuTwo: "", NoteName: "食堂左" },
        { ID: 12, MenuOne: "食堂", MenuTwo: "", NoteName: "食堂右" },
      ];

      let arr = [];

      list.map((item) => {
        let isHasOne = arr.findIndex((ele) => ele.label == item.MenuOne);
        if (isHasOne === -1) {
          let id = (arr.length + 1).toString();
          arr.push({
            id,
            label: item.MenuOne,
            child: [
              {
                label: item.MenuTwo,
                child: [
                  {
                    id: id + "-1",
                    label: item.NoteName,
                  },
                ],
              },
            ],
          });
        } else {
          let isHasTwo = arr[isHasOne].child.findIndex(
            (ele) => ele.label == item.MenuTwo
          );
          let sub = arr[isHasOne].child.reduce((a, b) => {
            let result = b.child.concat(a.child);
            b.child = result;
            return b;
          });
          if (isHasTwo === -1) {
            arr[isHasOne].child.push({
              label: item.MenuTwo,
              child: [
                {
                  id: arr[isHasOne].id + "-" + (sub.child.length + 1),
                  label: item.NoteName,
                },
              ],
            });
          } else {
            arr[isHasOne].child[isHasTwo].child.push({
              id: arr[isHasOne].id + "-" + (sub.child.length + 1),
              label: item.NoteName,
            });
          }
        }
      });

      console.log("arr", arr);