如何在Javascript中将字符串数组转换为特定的树结构

Question

I get a list of file paths from the backend, it represents a folder structure and looks like this:

paths = ["path/to/file1.doc", "path/to/file2.doc", "foo/bar.doc]

The lengths of the paths are arbitrary. In order to use a file tree component ( angular2-tree-component ) I need to transform this data into the following format :

nodes = [
    {
        "name": "path",
        "children": [
            {
                "name": "to",
                "children": [
                    {"name": "file1.doc"},
                    {"name": "file2.doc"}
                ]
            }
        ]
    },
    {
        "name": "foo",
        "children": [
            {"name": "bar.doc"}
        ]
    }
]

I think the most efficient way to transform the data is to

1. Map the array with the files mirroring a tree structure first and then to
2. Iterate over every key in order to finalise the "children/parent" relations.

Step one:

transformToTree(data) {
    const tree = {};
    function addPathsToTree(paths) {
        let map = tree
        paths.forEach(function(item) {
            map[item] = map[item] || {};
            map = map[item];
        });
    }
    data.forEach(function(path) {
        let pathPart = path.split('/');
        addPathsToTree(pathPart);
    });
    return pathTree;
}

When passing "nodes" into the transformToTree function (transformToTree(nodes)), I get the following result:

{
    "path": {
        "to": {
            "file1.doc": {},
            "file2.doc": {}
        }
    },
    "foo": {
        "bar": {}
    }
}

I don't know how to proceed from here = how to iterate over all the keys and values while building the final array in the required structure.

There are a few examples like this or that on SO, but I was not able to understand how I could adapt them to my needs.

Answer 1

I would go with two nested loops, one for pathes and one for the splitted names and find the name or create new objects.

 var paths = ["path/to/file1.doc", "path/to/file2.doc", "foo/bar.doc"], result = []; paths.reduce((r, path) => { path.split('/').reduce((o, name) => { var temp = (o.children = o.children || []).find(q => q.name === name); if (!temp) o.children.push(temp = { name }); return temp; }, r); return r; }, { children: result }); console.log(result);

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