``` const arr = [{
id: 2,
name: '部门B',
parentId: 0
},
{
id: 20,
name: '部门cccC',
parentId: 0
},
{
id: 3,
name: '部门C',
parentId: 1
},
{
id: 1,
name: '部门A',
parentId: 2
},
{
id: 4,
name: '部门D',
parentId: 1
},
{
id: 5,
name: '部门E',
parentId: 2
},
{
id: 6,
name: '部门F',
parentId: 4
},
{
id: 7,
name: '部门G',
parentId: 2
},
{
id: 8,
name: '部门H',
parentId: 4
}
]
function fn(obj,n){
let result = [];
loop(obj,n)
function loop(obj,n){
let tmp = {
num:n,
list:[]
};
let ccc= [];
for(let i=obj.length; i--; i>0){
obj[i]['children'] = [];
if(obj[i].parentId == n){
tmp.list.push(obj[i])
tmp.num = obj[i].parentId;
}else{
ccc.push(obj[i])
}
}
if(tmp.list.length>0){
result.push(tmp);
}
n++;
if(ccc.length>0){
loop(ccc,n)
}
}
for(let i=result.length-1; i--; i>0){
result[i].list.filter(item=>{
item.children.push(result[i+1].list)
})
}
return result[0].list;
}
console.log(fn(arr,0))
