方法递归更新一个值到顶部

Question

我正在尝试创建一种递归方法，当您单击层次结构时，所有父项都将被启用。

我知道如何使递归方法自上而下，例如，找到一个孩子，但我不知道如何使递归方法自上而下。

例如：

const data =  [{
    "id": 1,
    "parentId": null,
    "selected": false,
    "children": [{
        "id": 2,
        "parentId": 1,
        "selected": false,
        "children": [{
            "id": 3,
            "parentId": 2,
            "selected": false,
            "children": [{
                "id": 4,
                "parentId": 3,
                "selected": false,
                "children": []
            }]
        }]
    }]
 }, {
    "id": 1,
    "parentId": null,
    "selected": true,
    "children": []
 }, {
    "id": 1,
    "parentId": null,
    "selected": true,
    "children": []
 }]

When the item with id4 is selected, the selectedproperty of all its ancestors should be set to true.

Answer 1

您可以简单地迭代，直到parentId当前节点的 变为null。

const data = [{ id: 1, parentId: null, selected: false, children: [{id: 2, parentId: 1, selected: false, children: [{id: 3, parentId: 2, selected: false, children: [{id: 4, parentId: 3, selected: false, children: []}]} ]} ] }, { id: 5, parentId: null, selected: true, children: [] }, { id: 6, parentId: null, selected: true, children: [] } ];
const getById = id => {
  const get = arr => {
    for(const x of arr){
      if(x.id === id) return x;
      const res = get(x.children || []);
      if(res) return res;
    }
  }
  return get(data);
}
let node = getById(4);
while(node.parentId != null){
  node = getById(node.parentId);
  node.selected = true;
}
console.log(data);