搜索并列出目录/子目录中的所有文件到 ListBox

Question

好的，感谢@sircodesalot

Public Sub AppendFilesFromDirectory(ByVal path As DirectoryInfo, ByVal files As List(Of FileInfo)) For Each file As FileInfo In CurrentFolder.GetFiles() files.Add(file) Next For Each subfolder As DirectoryInfo In CurrentFolder.GetDirectories() AppendFilesFromDirectory(subfolder, files) Next End Sub

Dim files As New List(Of FileInfo) AppendFilesFromDirectory(New DirectoryInfo(FolderBrowserDialog1.SelectedPath), files) For Each file As FileInfo In files ListBox1.Items.Add(file.FullName) Next

解决了一些我的老问题

它适用于其中包含子文件夹的文件夹，但如果一个文件夹只有文件，那么它会变成一个循环，不断地将文件添加到 myList。

有什么建议可以避免吗？ @sircodesalot 好心地试图向我解释，但无论我尝试什么，我都无法做到..

非常感谢您的帮助！

Answer 1

首先了解一个简单的递归函数，例如factorial。例如：

int factorial(int number) {
    if (number < 1)
        return 1;
    else
        return factorial(number - 1) * number;
}

基本上，如果我们要计算factorial(5)，那么就是：

 factorial(5) * factorial(4) * factorial (3) * factorial(2) * factorial(1)

或更抽象地说：

 factorial(n) * factorial(n - 1) * factorial (n - 2) * ... * factorial (1)

所以我们用一个递减的值来调用函数本身来计算结果。

上面的问题同样适用。如果我们想获取所有的子目录，那么我们要做的就是：

(1) List all the files in the current folder
(2) For the files that are directories, repeat step one.

换句话说：

List<Folder> readAllFiles() {
    List<Folder> folders = new List<Folder>();

    readAllFilesRecursively("C:/", folders);
}

List<Folder> readAllFilesRecursively(String directory, List<Folder> folders) {
     Folder currentDirectory = castTheStringToADirectorySomehow(directory);

     // Add the current folder to the list.
     folders.add(currentDirectory);


     // ** HERE IS WHAT YOU'RE MISSING ** //
     // Re-call the same function on the sub folder, passing in our list
     // so that the subfolder items can be added to the list.
     foreach (Folder subfolder in currentDirectory.subFolders()) {
          readAllFilesRecursively(subFolder.pathString(), folders);
     }

     // Return the folder list.
     return folders;
}

编辑：

所以这对我有用，但显然你必须将其更改为 VB。另外，我使用的是 Mac，所以您会注意到路径格式有点不同：

class Program {
    public static void Main() {

        List<FileInfo> files = new List<FileInfo> ();
        AppendFilesFromDirectory (new DirectoryInfo("/Users/sircodesalot/Desktop/Dev"), files);

        foreach (FileInfo file in files) {
            Console.WriteLine (file.FullName);
        }
    }

    public static void AppendFilesFromDirectory(DirectoryInfo currentFolder, List<FileInfo> files) {

        foreach (FileInfo file in currentFolder.GetFiles()) {
            files.Add(file);
        }

        // This if statement is unneccesary, but I'll add it for clarity 
        // to explain the concept of a base case. We don't really need it though
        // since the 'foreach' statement won't execute if there aren't any items.

        if (currentFolder.GetDirectories().Count() > 0) {

            // Process the subfolders
            foreach (DirectoryInfo subfolder in currentFolder.GetDirectories()) {
                AppendFilesFromDirectory (subfolder, files);
            }
        }
    }
}