javascript - 如何从 flatTreeNode 填充树？

Question

我有 treeFlatNode 数组，我想以树格式构建它。或者我可以直接以 Angular 在树中显示这个数组吗？

data=[
  {
   expandable: true
   level: 0
   name: "2021-12-31"
   path: null
  },
  {
   expandable: false
   level: 2
   name: "A.txt"
   path: "2021-12-31/B/C/A.txt"
  }
]

required format
tree=[
   name:"2021-12-03",
   children:[
      name:"B",
      children:[{
         name:"C"
         children:[{
             name:"A.txt"
             children:[]
         }]
     }]
   ]
]

Answer 1

您可以使用一个对象 (map) 将(子)路径映射到最终树中的节点。如果尚不存在，则会将其添加到父级的子级中。

由于您的树结构实际上代表一个森林(可以有多个根)，因此我将结果变量命名为 forest 而不是 tree

片段:

function toForest(data) {
    const roots = [];
    const map = {};
    for (const obj of data) {
        let key = "";
        let children = roots;
        for (const name of (obj.path ?? obj.name).split("/")) {
            let child = map[key += "/" + name]; 
            if (!child) children.push(map[key] = child = { name, children: [] });
            ({children} = child);
        }
    }
    return roots;
}

// Example run
let data = [{expandable: true,level: 0,name: "2021-12-31",path: null}, {expandable: false,level: 2,name: "A.txt",path: "2021-12-31/B/C/A.txt"}];
let forest = toForest(data);
console.log(forest);