最顶层的parent 为 -1 ，其余的 parent都是为 上⼀层节点的id
let arr = [
{ id: 0, name: '1', parent: -1, childNode: [] },
{ id: 1, name: '1', parent: 0, childNode: [] },
{ id: 99, name: '1-1', parent: 1, childNode: [] },
{ id: 111, name: '1-1-1', parent: 99, childNode: [] },
{ id: 66, name: '1-1-2', parent: 99, childNode: [] },
{ id: 1121, name: '1-1-2-1', parent: 112, childNode: [] },
{ id: 12, name: '1-2', parent: 1, childNode: [] },
{ id: 2, name: '2', parent: 0, childNode: [] },
{ id: 21, name: '2-1', parent: 2, childNode: [] },
{ id: 22, name: '2-2', parent: 2, childNode: [] },
{ id: 221, name: '2-2-1', parent: 22, childNode: [] },
{ id: 3, name: '3', parent: 0, childNode: [] },
{ id: 31, name: '3-1', parent: 3, childNode: [] },
{ id: 32, name: '3-2', parent: 3, childNode: [] }
]
const arrtotree = (arr,parentId) => {
const filterArr = arr.filter(item => {
return parentId === undefined ? item.parent === -1 : item.parent === parentId
})
filterArr.map(item => {
item.childNode = arrtotree(arr, item.id)
return item
})
return filterArr
}
console.log(arrtotree(arr0));
