C# 从路径列表填充树视图

populate treeview from a list of path

提问by

I'm trying to populate a treeview from a list of folder path, for example:

我正在尝试从文件夹路径列表中填充树视图，例如：

C:\WINDOWS\addins
C:\WINDOWS\AppPatch
C:\WINDOWS\AppPatch\MUI
C:\WINDOWS\AppPatch\MUI0C
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI09

with an ouput like this:

有这样的输出：

├───addins
├───AppPatch
│   └───MUI
│       └───040C
├───Microsoft.NET
│   └───Framework
│       └───v2.0.50727
│           └───MUI
│               └───0409

Notice there's no 'C:\WINDOWS\Microsoft.NET' or 'C:\WINDOWS\Microsoft.NET\Framework' in the list. I've been working on this for almost two days and there's a bunch of bug in my code. Hope I can get help from here.

请注意，列表中没有“C:\WINDOWS\Microsoft.NET”或“C:\WINDOWS\Microsoft.NET\Framework”。我已经为此工作了将近两天，我的代码中有一堆错误。希望我能从这里得到帮助。

Thanks.

谢谢。

Eric

埃里克

回答by Dan Diplo

Here's some very old code I once used to create an ASP.NET treeview from code (assuming TreeView has an ID of TreeViewFolders):

这是我曾经用来从代码创建 ASP.NET 树视图的一些非常旧的代码（假设 TreeView 的 ID 为 TreeViewFolders）：

protected void Page_Load(object sender, EventArgs e)
{
    GenerateTreeView(@"C:\WINDOWS\");
}

private void GenerateTreeView(string rootPath)
{
    GetFolders(System.IO.Path.GetFullPath(rootPath), TreeViewFolders.Nodes);
    TreeViewFolders.ExpandDepth = 1;
}

// recursive method to load all folders and files into tree
private void GetFolders(string path, TreeNodeCollection nodes)
{
    // add nodes for all directories (folders)
    string[] dirs = Directory.GetDirectories(path);
    foreach (string p in dirs)
    {
        string dp = p.Substring(path.Length);
        nodes.Add(Node("", p.Substring(path.Length), "folder"));
    }

    // add nodes for all files in this directory (folder)
    string[] files = Directory.GetFiles(path, "*.*");
    foreach (string p in files)
    {
        nodes.Add(Node(p, p.Substring(path.Length), "file"));
    }

    // add all subdirectories for each directory (recursive)
    for (int i = 0; i < nodes.Count; i++)
    {
        if (nodes[i].Value == "folder")
            GetFolders(dirs[i] + "\", nodes[i].ChildNodes);
    }
}

// create a TreeNode from the specified path, text and type
private TreeNode Node(string path, string text, string type)
{
    TreeNode n = new TreeNode();
    n.Value = type;
    n.Text = text;
    return n;
}

回答by ehosca

private void Form1_Load(object sender, EventArgs e)
    {
        var paths = new List<string>
                        {
                            @"C:\WINDOWS\AppPatch\MUI0C",
                            @"C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727",
                            @"C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI",
                            @"C:\WINDOWS\addins",
                            @"C:\WINDOWS\AppPatch",
                            @"C:\WINDOWS\AppPatch\MUI",
                            @"C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI09"
                        };

        treeView1.PathSeparator = @"\";

        PopulateTreeView(treeView1, paths, '\');
}


private static void PopulateTreeView(TreeView treeView, IEnumerable<string> paths, char pathSeparator)
    {
        TreeNode lastNode = null;
        string subPathAgg;
        foreach (string path in paths)
        {
            subPathAgg = string.Empty;
            foreach (string subPath in path.Split(pathSeparator))
            {
                subPathAgg += subPath + pathSeparator;
                TreeNode[] nodes = treeView.Nodes.Find(subPathAgg, true);
                if (nodes.Length == 0)
                    if (lastNode == null)
                        lastNode = treeView.Nodes.Add(subPathAgg, subPath);
                    else
                        lastNode = lastNode.Nodes.Add(subPathAgg, subPath);
                else
                    lastNode = nodes[0];
            }
        }
    }

回答by Sajitha Rathnayake

ehosca answer correcr, but there is a little problem, when I change paths to like this

ehosca 回答正确，但有一个小问题，当我改变路径时

C:\WINDOWS\AppPatch\MUI0C
D:\WIS\Microsoft.NET\Framework\v2.0.50727
E:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI
C:\WINDOWS\addins
C:\WINDOWS\AppPatch
C:\WINDOWS\AppPatch\MUI
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI09

It will popoulate treeview like this.

它将像这样填充树视图。

But adding some extra code we can avoid this situation. So I changed the code in PopulateTreeView

但是添加一些额外的代码我们可以避免这种情况。所以我改变了 PopulateTreeView 中的代码

private static void PopulateTreeView(TreeView treeView, string[] paths, char pathSeparator)
        {
            TreeNode lastNode = null;
            string subPathAgg;
            foreach (string path in paths)
            {
                subPathAgg = string.Empty;
                foreach (string subPath in path.Split(pathSeparator))
                {
                    subPathAgg += subPath + pathSeparator;
                    TreeNode[] nodes = treeView.Nodes.Find(subPathAgg, true);
                    if (nodes.Length == 0)
                        if (lastNode == null)
                            lastNode = treeView.Nodes.Add(subPathAgg, subPath);
                        else
                            lastNode = lastNode.Nodes.Add(subPathAgg, subPath);
                    else
                        lastNode = nodes[0];
                }
                lastNode = null; // This is the place code was changed

            }
        }

Now it works fine like this

现在它像这样工作正常

回答by kaytes

I took your code, and it work very well, but i made just a little modification for improving the load speed when it is used whit a large list of files it seems like find operation, and string operations generally are very slow

我拿了你的代码，它工作得很好，但我做了一点修改，以提高加载速度，当它使用大量文件时，它看起来像查找操作，而字符串操作通常很慢

private TreeNode PopulateTreeNode2(string[] paths, string pathSeparator)
    {
        if (paths == null)
            return null;

        TreeNode thisnode = new TreeNode();
        TreeNode currentnode;
        char[] cachedpathseparator = pathSeparator.ToCharArray();
        foreach (string path in paths)            {
            currentnode = thisnode;
            foreach (string subPath in path.Split(cachedpathseparator))
            {
                if (null == currentnode.Nodes[subPath])
                    currentnode = currentnode.Nodes.Add(subPath, subPath);
                else
                    currentnode = currentnode.Nodes[subPath];                   
            }
        }

        return thisnode;
    }

then you can use:

那么你可以使用：

string[] paths =  {
                        @"C:\WINDOWS\AppPatch\MUI0C",
                        @"D:\WINDOWS\Microsoft.NET\Framework\v2.0.50727",
                        @"E:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI",
                        @"C:\WINDOWS\addins",
                        @"C:\WINDOWS\AppPatch",
                        @"C:\WINDOWS\AppPatch\MUI",
                        @"C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\MUI09"
                    };
TreeView treeview = new TreeView();
treeview.Nodes.Add(PopulateTreeNode2(paths, "\"));

NOTE: maybe some string sensitivity check will be needed in both solutions, in order to prevent some folders re creations.

注意：可能在两种解决方案中都需要进行一些字符串敏感性检查，以防止重新创建某些文件夹。

because some url could be pointing to the same folder on the disk but spelled different such as: Windows ; WinDOWs , WINDOWS

因为某些 url 可能指向磁盘上的同一个文件夹，但拼写不同，例如： Windows ; 窗口

回答by ykm29

for a linq'y version:

对于 linq'y 版本：

public static TreeNode MakeTreeFromPaths(List<string> paths, string rootNodeName = "", char separator = '/')
{
    var rootNode = new TreeNode(rootNodeName);
    foreach (var path in paths.Where(x => !string.IsNullOrEmpty(x.Trim()))) {
        var currentNode = rootNode;
        var pathItems = path.Split(separator);
        foreach (var item in pathItems) {
            var tmp = currentNode.Nodes.Cast<TreeNode>().Where(x => x.Text.Equals(item));
            currentNode = tmp.Count() > 0 ? tmp.Single() : currentNode.Nodes.Add(item);
        }
    }
    return rootNode;
}

回答by Santosh Kokatnur

private void Form2_Load(object sender, EventArgs e)
{
    treeView1.CheckBoxes = true;

    foreach (TreeNode node in treeView1.Nodes)
    {
        node.Checked = true;
    }

    string[] drives = Environment.GetLogicalDrives();

    foreach (string drive in drives)
    {
        // treeView1.Nodes[0].Nodes[1].Checked = true;
        DriveInfo di = new DriveInfo(drive);
        int driveImage;

        switch (di.DriveType)   
        {
            case DriveType.CDRom:
                driveImage = 3;
                break;
            case DriveType.Network:
                driveImage = 6;
                break;
            case DriveType.NoRootDirectory:
                driveImage = 8;
                break;
            case DriveType.Unknown:
                driveImage = 8;
                break;
            default:
                driveImage = 2;
                break;
        }

        TreeNode node = new TreeNode(drive.Substring(0, 1), driveImage, driveImage);
        node.Tag = drive;

        if (di.IsReady == true)
             node.Nodes.Add("...");

        treeView1.Nodes.Add(node);          
    }

    foreach (TreeNode node in treeView1.Nodes)
    {
        node.Checked = true;
    }
}

private void treeView1_BeforeExpand(object sender, TreeViewCancelEventArgs e)
{
    {
        if (e.Node.Nodes.Count > 0)
        {
            if (e.Node.Nodes[0].Text == "..." && e.Node.Nodes[0].Tag == null)
            {
                e.Node.Nodes.Clear();

                string[] dirs = Directory.GetDirectories(e.Node.Tag.ToString());

                foreach (string dir in dirs)
                {
                    DirectoryInfo di = new DirectoryInfo(dir);
                    TreeNode node = new TreeNode(di.Name, 0, 1);
                    node.Checked = true;

                    try
                    {
                        node.Tag = dir;
                        if (di.GetDirectories().Count() > 0)
                            node.Nodes.Add(null, "...", 0, 0).Checked = node.Checked;
                    }
                    catch (UnauthorizedAccessException)
                    {
                        node.ImageIndex = 12;
                        node.SelectedImageIndex = 12;
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show(ex.Message, "DirectoryLister", MessageBoxButtons.OK,
                        MessageBoxIcon.Error);
                    }
                    finally
                    {
                        node.Checked = e.Node.Checked;
                        e.Node.Nodes.Add(node);
                    }
                }
            }
        }
    }              
}

private void treeView1_AfterCheck(object sender, TreeViewEventArgs e)
{
    button1.Enabled = false;
    TreeNode node = e.Node;
    bool is_checked = node.Checked;
    foreach (TreeNode childNode in e.Node.Nodes)
    {
        childNode.Checked = e.Node.Checked;
    }
    treeView1.SelectedNode = node;
 }

回答by OSA413

I've managed to create a tree from path list using only forcycles. And it looks like it is the simpliest answer of this question at this moment.

我设法仅使用for循环从路径列表创建了一个树。看起来这是目前这个问题最简单的答案。

Use this block of code to create a tree. listis the list of your files or folders, treeView1is your TreeView.

使用此代码块创建一棵树。list是您的文件或文件夹的列表，treeView1是您的 TreeView。

//Creates a tree from given path list
foreach (string path in list)
{
    TreeNodeCollection nodes = treeView1.Nodes;

    foreach (string path_part in path.Split('\'))
    {
        //Here it adds a new node (file or folder)
        if (!nodes.ContainsKey(path_part))
            nodes.Add(path_part, path_part);
        //Go one node deeper
        nodes = nodes[path_part].Nodes;
    }
}

Note - this may break if you use it with paths that start with the path separator (e.g. /home/user)

注意 - 如果您将它与以路径分隔符开头的路径一起使用，这可能会中断（例如/home/user）

And if you want to remove common parts of your paths (or remove single parent nodes), use this block of code right after the previous one:

如果您想删除路径的公共部分（或删除单个父节点），请在上一个代码块之后立即使用此代码块：

//This removes "single" TreeNodes (common paths)
while (treeView1.Nodes.Count == 1)
{
    //This "unpacks" child TreeNodes from the only parent TreeNode
    for (int i = 0; i < treeView1.Nodes[0].Nodes.Count; i++)
        treeView1.Nodes.Add(treeView1.Nodes[0].Nodes[i]);
    //This removes parent TreeNode
    treeView1.Nodes.RemoveAt(0);
}

This will generate an empty tree if all of your paths are the same.

如果所有路径都相同，这将生成一棵空树。