Question

I’m using MongoDB and I need to write an algorithm to fill the following classes, to build a tree directory structures:

public class Dir 
{
    public string name { get; set; }
    public string hash { get; set; }
    public bool read { get; set; }
    public bool write { get; set; }
    public Dir[] dirs { get; set; }
}

I will get form MongoDB a List strings of the folders like this, distinct and sorted (empty string is the root):

 Folder1
 Folder2
 Folder2/ChildFolder
 Folder2/ChildFolder2
 Folder2/ChildFolder3
 Folder2/ChildFolder3/Folderrrr
 Folder2/ChildFolder3/Hi
 ""

I should have a Dir object which is the root folder, and inside that one I should have an array of directories, on each directory I could have another array of directories and so one…

Any idea? Thanks for any help

Answer 1

Works fine with your example data, but may be need to make some updates in future

    static void Main(string[] args)
    {
        var folders = new[] { "Folder1","Folder2","Folder2/ChildFolder","Folder2/ChildFolder2","Folder2/ChildFolder3",
                              "Folder2/ChildFolder3/Folderrrr", "Folder2/ChildFolder3/Hi"
                            };
        var root = new Dir("Root");
        foreach (var folder in folders)
        {
            BuildTree(folder, root);
        }
    }

    private static void BuildTree(string path, Dir parent)
    {
        if (parent == null) return;

        if (path.Contains("/"))
        {
            var dir = path.Substring(0, path.IndexOf("/"));
            var newPath = path.Substring(dir.Length + 1);
            Dir addNodeTo;
            if (!parent.Contains(dir))
            {
                var newParent = new Dir(dir);
                parent.Dirs.Add(newParent);
                addNodeTo = newParent;
            }
            else
            {
                addNodeTo = parent.Get(dir);
            }
            BuildTree(newPath, addNodeTo);
        }
        else
        {
            if (!parent.Contains(path))
                parent.Dirs.Add(new Dir(path));
        }
    }

 public class Dir
 {
    public string Name { get; private set; }
    public string Hash { get; set; }
    public bool Read { get; set; }
    public bool Write { get; set; }
    public List<Dir> Dirs { get; private set; }

    public Dir(string name)
    {
        Name = name;
        Dirs = new List<Dir>();
    }

    public bool Contains(string name)
    {
        return Dirs.Any(d => d.Name.Equals(name));
    }

    public Dir Get(string name)
    {
        return Dirs.FirstOrDefault(d => d.Name.Equals(name));
    }

    public override string ToString()
    {
        return Name;
    }
}