json数据都在同一级怎么转换为树状结构

[村口的二狗子]

一二三四级菜单数据都在同一级怎么转成树状结构

[scscms太阳光]

这种很多种方法可以转。曾布置同样的作业每个学生写的都不一样。

[scscms太阳光]

   let json = [
        {
            index:0,
            CategoryDepth:0,
            CategoryId:'001',
            CategoryName:'一级菜单',
            CategoryCategoryId:'0'
        },
        {
            index:1,
            CategoryDepth:1,
            CategoryId:'002',
            CategoryName:'二级菜单',
            CategoryCategoryId:'001'
        },
        {
            index:2,
            CategoryDepth:1,
            CategoryId:'0022',
            CategoryName:'二级菜单',
            CategoryCategoryId:'001'
        },
        {
            index:3,
            CategoryDepth:3,
            CategoryId:'003',
            CategoryName:'三级菜单',
            CategoryCategoryId:'002'
        },
        {
            index:4,
            CategoryDepth:4,
            CategoryId:'004',
            CategoryName:'四级菜单',
            CategoryCategoryId:'003'
        }
    ]
    let arr = JSON.parse(JSON.stringify(json))//深克隆一份
    arr.forEach(obj => {
        !Array.isArray(obj.child) && (obj.child = [])
        arr.forEach(o => {
            if (o.CategoryCategoryId === obj.CategoryId) {
                obj.child.push(o)
            }
        })
    })
    arr = arr.filter(obj => obj.CategoryCategoryId === '0')
    console.log(arr)