对 LINQ 中的路径列表进行排序？

Question

假设我有以下文件夹：

New Folder
- New Folder
- New Folder (2)
- New Folder (3)
- New Folder (4)
New Folder (2)
New Folder (3)
New Folder (4)

和一个查询

from s in Directory.GetDirectories(@"D:\Project\uploads", "*.*", SearchOption.AllDirectories)
select s

结果：

D:\Project\uploads\New Folder
D:\Project\uploads\New Folder (2)
D:\Project\uploads\New Folder (3)
D:\Project\uploads\New Folder (4)
D:\Project\uploads\New Folder\New Folder
D:\Project\uploads\New Folder\New Folder (2)
D:\Project\uploads\New Folder\New Folder (3)
D:\Project\uploads\New Folder\New Folder (4)

是否有办法按正确的顺序对列表进行排序？我期望它是：

D:\Project\uploads\New Folder
D:\Project\uploads\New Folder\New Folder
D:\Project\uploads\New Folder\New Folder (2)
D:\Project\uploads\New Folder\New Folder (3)
D:\Project\uploads\New Folder\New Folder (4)
D:\Project\uploads\New Folder (2)
D:\Project\uploads\New Folder (3)
D:\Project\uploads\New Folder (4)

任何帮助将不胜感激！

Answer 1

这并不像我想象的那么微不足道。 可能最明智的解决方案（除了递归地构建列表之外）是为此实现一个比较器来进行排序。

class DirectorySorter : IComparer<string>
{
    public int Compare(string x, string y)
    {
        return StringComparer.Ordinal.Compare(x.Replace(Path.DirectorySeparatorChar, '\0'),
                                        y.Replace(Path.DirectorySeparatorChar, '\0'));
        var xPaths = x.Split(Path.DirectorySeparatorChar);
        var yPaths = y.Split(Path.DirectorySeparatorChar);
        var minLength = Math.Min(xPaths.Length, yPaths.Length);
        for (int i = 0; i < minLength; i++)
        {
            var ires = xPaths[i].CompareTo(yPaths[i]);
            if (ires != 0) return ires;
        }
        var lres = xPaths.Length.CompareTo(yPaths.Length);
        if (lres == 0)
        {
            return lres;
        }
        else if (lres < 0)
        {
            var i = y.LastIndexOf(Path.DirectorySeparatorChar);
            return x.Length == i ? lres : -lres;
        }
        else //if (lres > 0)
        {
            var i = x.LastIndexOf(Path.DirectorySeparatorChar);
            return y.Length == i ? lres : -lres;
        }
    }
}

（看到 Steck 的答案表明我几乎已经达到了最初的水平。只是我需要使用序数字符串比较器。所以事实证明它可以使用该更改。）

另一方面，我们可以使用目录结构来简化此任务并且不实现比较器。

var query = Directory
    .EnumerateDirectories(@"D:\Project\uploads", "*", SearchOption.AllDirectories)
    .OrderBy(name => name.Replace(Path.DirectorySeparatorChar, '\0'), StringComparer.Ordinal);

Answer 2

private class Comparer : IComparer<string>
{
    public int Compare(string x, string y)
    {
        return StringComparer.Ordinal.Compare(x.Replace(Path.DirectorySeparatorChar, '\0'),
                                                y.Replace(Path.DirectorySeparatorChar, '\0'));
    }
}

进而

var source = Directory.GetDirectories(@"D:\Project\uploads", "*.*", SearchOption.AllDirectories)
var target = source.OrderBy(x => x, new Comparer()).ToArray();

Answer 3

关于默认顺序，您唯一需要更改的是确保 \ 字符始终被视为字母表中的第一个字母。我没有确切的答案如何实现这一点，但是：

• 如果您找到一种方法将字符串中的 \ 替换为比所有其他字符都小的字符，并使用此替换字符串作为键。

• 您可以使用 Array.Sort 并实现重新实现字符串比较的字符串比较器，但对有关 \ 字符的附加规则进行编码。

Answer 4

使用.NET 4.0 尝试一下

 Directory.EnumerateDirectories(@"D:\Project\uploads", "*.*", SearchOption.AllDirectories) 

，它可能会达到您的预期。如果没有，您可以明确地执行此操作：

 Directory.GetDirectories(@"D:\Project\uploads")
      .SelectMany(dir => dir.GetDirectories().OrderBy(sub => sub.Name))

最后您可能会执行以下操作：

 from s in Directory.GetDirectories(@"D:\Project\uploads", "*.*", SearchOption.AllDirectories)
 order by s.Parent.Name, s.Name
 select s

 from s in Directory.GetDirectories(@"D:\Project\uploads", "*.*", SearchOption.AllDirectories)
 let members = s.Name.Split(new [] {Path.SeparatorChar})
 order by members[2], s.Name
 select s

以获得更多控制/灵活性。根据您的需求选择最简单的方法

Answer 5

感谢您的评论和回答，

我认为递归的生活会更容易

void Main()
{
    string rootFolder = @"D:\Project\uploads";

    string[] f = Directory.GetDirectories(rootFolder, "*.*", SearchOption.AllDirectories);

    Func<string, string[]> build = null;

    build = (p) => {
        return (from x in f where Path.GetDirectoryName(x) == p
                from y in new string[]{ x }.Union(build(x)) select y).ToArray();
    };

    f = build(rootFolder).Dump();
}