How to recursively list all the files in a directory in C#?

How to recursively list all the files in a directory and child directories in C#?

Note that in .NET 4.0 there are (supposedly) iterator-based (rather than array-based) file functions built in:

foreach (string file in Directory.EnumerateFiles(path, "*.*", SearchOption.AllDirectories))
{
    Console.WriteLine(file);
}

At the moment I'd use something like below; the inbuilt recursive method breaks too easily if you don't have access to a single sub-dir...; the Queue<string> usage avoids too much call-stack recursion, and the iterator block avoids us having a huge array.

static void Main() {
    foreach (string file in GetFiles(SOME_PATH)) {
        Console.WriteLine(file);
    }
}

static IEnumerable<string> GetFiles(string path) {
    Queue<string> queue = new Queue<string>();
    queue.Enqueue(path);
    while (queue.Count > 0) {
        path = queue.Dequeue();
        try {
            foreach (string subDir in Directory.GetDirectories(path)) {
                queue.Enqueue(subDir);
            }
        }
        catch(Exception ex) {
            Console.Error.WriteLine(ex);
        }
        string[] files = null;
        try {
            files = Directory.GetFiles(path);
        }
        catch (Exception ex) {
            Console.Error.WriteLine(ex);
        }
        if (files != null) {
            for(int i = 0 ; i < files.Length ; i++) {
                yield return files[i];
            }
        }
    }
}

This article covers all you need. Except as opposed to searching the files and comparing names, just print out the names.

It can be modified like so:

static void DirSearch(string sDir)
{
    try
    {
        foreach (string d in Directory.GetDirectories(sDir))
        {
            foreach (string f in Directory.GetFiles(d))
            {
                Console.WriteLine(f);
            }
            DirSearch(d);
        }
    }
    catch (System.Exception excpt)
    {
        Console.WriteLine(excpt.Message);
    }
}

Added by barlop

GONeale mentions that the above doesn't list the files in the current directory and suggests putting the file listing part outside the part that gets directories. The following would do that. It also includes a Writeline line that you can uncomment, that helps to trace where you are in the recursion that may help to show the calls to help show how the recursion works.

            DirSearch_ex3("c:\\aaa");
            static void DirSearch_ex3(string sDir)
            {
                //Console.WriteLine("DirSearch..(" + sDir + ")");
                try
                {
                    Console.WriteLine(sDir);

                    foreach (string f in Directory.GetFiles(sDir))
                    {
                        Console.WriteLine(f);
                    }

                    foreach (string d in Directory.GetDirectories(sDir))
                    {
                        DirSearch_ex3(d);
                    }
                }
                catch (System.Exception excpt)
                {
                    Console.WriteLine(excpt.Message);
                }
            }

Directory.GetFiles("C:\\", "*.*", SearchOption.AllDirectories)

Shortest record

string[] files = Directory.GetFiles(@"your_path", "*.jpg", SearchOption.AllDirectories);

In .NET 4.5, at least, there's this version that is much shorter and has the added bonus of evaluating any file criteria for inclusion in the list:

public static IEnumerable<string> GetAllFiles(string path, 
                                              Func<FileInfo, bool> checkFile = null)
{
    string mask = Path.GetFileName(path);
    if (string.IsNullOrEmpty(mask)) mask = "*.*";
    path = Path.GetDirectoryName(path);
    string[] files = Directory.GetFiles(path, mask, SearchOption.AllDirectories);

    foreach (string file in files)
    {
        if (checkFile == null || checkFile(new FileInfo(file)))
            yield return file;
    }
}

Use like this:

var list = GetAllFiles(mask, (info) => Path.GetExtension(info.Name) == ".html").ToList();

IEnumerable<string> GetFilesFromDir(string dir) =>
 Directory.EnumerateFiles(dir).Concat(
 Directory.EnumerateDirectories(dir)
          .SelectMany(subdir => GetFilesFromDir(subdir)));

Some excellent answers but these answers did not solve my issue.

As soon as a folder permission issue arises: "Permission Denied" the code fails. This is what I used to get around the "Permission Denied" issue:

private int counter = 0;

    private string[] MyDirectories = Directory.GetDirectories("C:\\");

    private void ScanButton_Click(object sender, EventArgs e)
    {
        Thread MonitorSpeech = new Thread(() => ScanFiles());
        MonitorSpeech.Start();
    }

    private void ScanFiles()
    {
        string CurrentDirectory = string.Empty;

        while (counter < MyDirectories.Length)
        {
            try
            {
                GetDirectories();
                CurrentDirectory = MyDirectories[counter++];
            }
            catch
            {
                if (!this.IsDisposed)
                {
                    listBox1.Invoke((MethodInvoker)delegate { listBox1.Items.Add("Access Denied to : " + CurrentDirectory); });
                }
            }
        }
    }

    private void GetDirectories()
    {
        foreach (string directory in MyDirectories)
        {
            GetFiles(directory);
        }
    }

    private void GetFiles(string directory)
    {
        try
        {
            foreach (string file in Directory.GetFiles(directory, "*"))
            {
                listBox1.Invoke((MethodInvoker)delegate { listBox1.Items.Add(file); });
            }
        }
        catch
        {
            listBox1.Invoke((MethodInvoker)delegate { listBox1.Items.Add("Access Denied to : " + directory); });
        }
    }

Hope this helps others.

In Framework 2.0 you can use (It list files of root folder, it's best the most popular answer):

static void DirSearch(string dir)
{
    try
    {
        foreach (string f in Directory.GetFiles(dir))
            Console.WriteLine(f);
        foreach (string d in Directory.GetDirectories(dir))
        {
            Console.WriteLine(d);
            DirSearch(d);
        }

    }
    catch (System.Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
}

A simple and clean solution

/// <summary>
/// Scans a folder and all of its subfolders recursively, and updates the List of files
/// </summary>
/// <param name="sFullPath">Full path of the folder</param>
/// <param name="files">The list, where the output is expected</param>
internal static void EnumerateFiles(string sFullPath, List<FileInfo> fileInfoList)
{
    try
    {
        DirectoryInfo di = new DirectoryInfo(sFullPath);
        FileInfo[] files = di.GetFiles();

        foreach (FileInfo file in files)
            fileInfoList.Add(file);

        //Scan recursively
        DirectoryInfo[] dirs = di.GetDirectories();
        if (dirs == null || dirs.Length < 1)
            return;
        foreach (DirectoryInfo dir in dirs)
            EnumerateFiles(dir.FullName, fileInfoList);

    }
    catch (Exception ex)
    {
        Logger.Write("Exception in Helper.EnumerateFiles", ex);
    }
}

I prefer to use DirectoryInfo because I can get FileInfo's, not just strings.

        string baseFolder = @"C:\temp";
        DirectoryInfo di = new DirectoryInfo(baseFolder);

        string searchPattern = "*.xml";

        ICollection<FileInfo> matchingFileInfos = di.GetFiles(searchPattern, SearchOption.AllDirectories)
            .Select(x => x)
            .ToList();

I do this in case in the future I need future filtering..based on the properties of FileInfo.

        string baseFolder = @"C:\temp";
        DirectoryInfo di = new DirectoryInfo(baseFolder);

        string searchPattern = "*.xml";

        ICollection<FileInfo> matchingFileInfos = di.GetFiles(searchPattern, SearchOption.AllDirectories)
            .Where(x => x.LastWriteTimeUtc < DateTimeOffset.Now)
            .Select(x => x)
            .ToList();

I can also resort back to strings if need be. (and still am future proofed for filters/where-clause stuff.

        string baseFolder = @"C:\temp";
        DirectoryInfo di = new DirectoryInfo(baseFolder);

        string searchPattern = "*.xml";

        ICollection<string> matchingFileNames = di.GetFiles(searchPattern, SearchOption.AllDirectories)
            .Select(x => x.FullName)
            .ToList();

Note that "." is a valid search pattern if you want to filer by extension.

This is how we can get files as FileInfo of its child directories,

var dir = new DirectoryInfo(rootPath);
FileInfo[] files = dir.GetFiles("*.*", SearchOption.AllDirectories);

private void GetFiles(DirectoryInfo dir, ref List<FileInfo> files)
{
    try
    {
        files.AddRange(dir.GetFiles());
        DirectoryInfo[] dirs = dir.GetDirectories();
        foreach (var d in dirs)
        {
            GetFiles(d, ref files);
        }
    }
    catch (Exception e)
    {
       
    }
}

To avoid the UnauthorizedAccessException, I use:

var files = GetFiles(@"C:\", "*.*", SearchOption.AllDirectories);
foreach (var file in files)
{
    Console.WriteLine($"{file}");
}

public static IEnumerable<string> GetFiles(string path, string searchPattern, SearchOption searchOption)
{
    var foldersToProcess = new List<string>()
    {
        path
    };

    while (foldersToProcess.Count > 0)
    {
        string folder = foldersToProcess[0];
        foldersToProcess.RemoveAt(0);

        if (searchOption.HasFlag(SearchOption.AllDirectories))
        {
            //get subfolders
            try
            {
                var subfolders = Directory.GetDirectories(folder);
                foldersToProcess.AddRange(subfolders);
            }
            catch (Exception ex)
            {
                //log if you're interested
            }
        }

        //get files
        var files = new List<string>();
        try
        {
            files = Directory.GetFiles(folder, searchPattern, SearchOption.TopDirectoryOnly).ToList();
        }
        catch (Exception ex)
        {
            //log if you're interested
        }

        foreach (var file in files)
        {
            yield return file;
        }
    }
}

If you only need filenames and since I didn't really like most of the solutions here (feature-wise or readability-wise), how about this lazy one?

private void Foo()
{
  var files = GetAllFiles("pathToADirectory");
  foreach (string file in files)
  {
      // Use can use Path.GetFileName() or similar to extract just the filename if needed
      // You can break early and it won't still browse your whole disk since it's a lazy one
  }
}

/// <exception cref="T:System.IO.DirectoryNotFoundException">The specified path is invalid (for example, it is on an unmapped drive).</exception>
/// <exception cref="T:System.UnauthorizedAccessException">The caller does not have the required permission.</exception>
/// <exception cref="T:System.IO.IOException"><paramref name="path" /> is a file name.-or-A network error has occurred.</exception>
/// <exception cref="T:System.IO.PathTooLongException">The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters and file names must be less than 260 characters.</exception>
/// <exception cref="T:System.ArgumentNullException"><paramref name="path" /> is null.</exception>
/// <exception cref="T:System.ArgumentException"><paramref name="path" /> is a zero-length string, contains only white space, or contains one or more invalid characters as defined by <see cref="F:System.IO.Path.InvalidPathChars" />.</exception>
[NotNull]
public static IEnumerable<string> GetAllFiles([NotNull] string directory)
{
  foreach (string file in Directory.GetFiles(directory))
  {
    yield return file; // includes the path
  }

  foreach (string subDir in Directory.GetDirectories(directory))
  {
    foreach (string subFile in GetAllFiles(subDir))
    {
      yield return subFile;
    }
  }
}

Some improved version with max lvl to go down in directory and option to exclude folders:

using System;
using System.IO;

class MainClass {
  public static void Main (string[] args) {

    var dir = @"C:\directory\to\print";
    PrintDirectoryTree(dir, 2, new string[] {"folder3"});
  }


  public static void PrintDirectoryTree(string directory, int lvl, string[] excludedFolders = null, string lvlSeperator = "")
  {
    excludedFolders = excludedFolders ?? new string[0];
	
    foreach (string f in Directory.GetFiles(directory))
    {
        Console.WriteLine(lvlSeperator+Path.GetFileName(f));
    } 
	
    foreach (string d in Directory.GetDirectories(directory))
    {
        Console.WriteLine(lvlSeperator + "-" + Path.GetFileName(d));
		
        if(lvl > 0 && Array.IndexOf(excludedFolders, Path.GetFileName(d)) < 0)
        {
          PrintDirectoryTree(d, lvl-1, excludedFolders, lvlSeperator+"  ");
        }
    }
  }
}

input directory:

-folder1
  file1.txt
  -folder2
    file2.txt
    -folder5
      file6.txt
  -folder3
    file3.txt
  -folder4
    file4.txt
    file5.txt

output of the function (content of folder5 is excluded due to lvl limit and content of folder3 is excluded because it is in excludedFolders array):

-folder1
  file1.txt
  -folder2
    file2.txt
    -folder5
  -folder3
  -folder4
    file4.txt
    file5.txt

Here's my angle on it, based on Hernaldo's, if you need to find files with names of a certain pattern, such as XML files that somewhere in their name contain a particular string:

// call this like so: GetXMLFiles("Platypus", "C:\\");
public static List<string> GetXMLFiles(string fileType, string dir)
{
    string dirName = dir; 
    var fileNames = new List<String>();
    try
    {
        foreach (string f in Directory.GetFiles(dirName))
        {
            if ((f.Contains(fileType)) && (f.Contains(".XML")))
            {
                fileNames.Add(f);
            }
        }
        foreach (string d in Directory.GetDirectories(dirName))
        {
            GetXMLFiles(fileType, d);
        }
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
    return fileNames;
}

Listing files and folders to model, custom implementation.
This creates a full listing of all files and folders starting from your start directory.

public class DirOrFileModel
    {
        #region Private Members

        private string _name;
        private string _location;
        private EntryType _entryType;

        #endregion

        #region Bindings

        public string Name
        {
            get { return _name; }
            set
            {
                if (value == _name) return;
                _name = value;
            }
        }

        public string Location
        {
            get { return _location; }
            set
            {
                if (value == _location) return;
                _location = value;
            }
        }
        
        public EntryType EntryType
        {
            get { return _entryType; }
            set
            {
                if (value == _entryType) return;
                _entryType = value;
            }
        }
        
        public ObservableCollection<DirOrFileModel> Entries { get; set; }

        #endregion

        #region Constructor

        public DirOrFileModel()
        {
            Entries = new ObservableCollection<DirOrFileModel>();
        }

        #endregion
    }
    
    public enum EntryType
    {
        Directory = 0,
        File = 1
    }

Method:

 static DirOrFileModel DirSearch(DirOrFileModel startDir)
        {
            var currentDir = startDir;
            try
            {
                foreach (string d in Directory.GetDirectories(currentDir.Location))
                {
                    var newDir = new DirOrFileModel
                    {
                        EntryType = EntryType.Directory,
                        Location = d,
                        Name = Path.GetFileName(d)
                    };
                    currentDir.Entries.Add(newDir);

                    DirSearch(newDir);
                }

                foreach (string f in Directory.GetFiles(currentDir.Location))
                {
                    var newFile = new DirOrFileModel
                    {
                        EntryType = EntryType.File,
                        Location = f,
                        Name = Path.GetFileNameWithoutExtension(f)
                    };
                    currentDir.Entries.Add(newFile);
                }

            }
            catch (Exception excpt)
            {
                Console.WriteLine(excpt.Message);
            }
            return startDir;
        }

Usage:

var dir = new DirOrFileModel
            {
                Name = "C",
                Location = @"C:\",
                EntryType = EntryType.Directory
            };

            dir = DirSearch(dir);

Short and simple solution

string dir = @"D:\PATH";

DateTime from_date = DateTime.Now.Date;
DateTime to_date = DateTime.Now.Date.AddHours(23);
var files = Directory.EnumerateFiles(dir, "*.*",SearchOption.AllDirectories).Select(i=>new FileInfo(i))
.Where(file=>file.LastWriteTime >= from_date && file.LastWriteTime <= to_date);
foreach(var fl in files)
	Console.WriteLine(fl.FullName);

This one helped me to get all files in a directory and sub directories, May be helpful for someone. [ Inspired from above answers ]

static void Main(string[] args)
    {
        try
        {
            var root = @"G:\logs";
            DirectorySearch(root);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
        Console.ReadKey();
    }





public static void DirectorySearch(string root, bool isRootItrated = false)
{
    if (!isRootItrated)
    {
        var rootDirectoryFiles = Directory.GetFiles(root);
        foreach (var file in rootDirectoryFiles)
        {
            Console.WriteLine(file);
        } 
    }

    var subDirectories = Directory.GetDirectories(root);
    if (subDirectories?.Any() == true)
    {
        foreach (var directory in subDirectories)
        {
            var files = Directory.GetFiles(directory);
            foreach (var file in files)
            {
                Console.WriteLine(file);
            }
            DirectorySearch(directory, true);
        }
    }
}

var d = new DirectoryInfo(@"C:\logs");
var list = d.GetFiles("*.txt").Select(m => m.Name).ToList();

Here is a version of B. Clay Shannon's code not static for excel-files:

class ExcelSearcher
{
    private List<string> _fileNames;

    public ExcelSearcher(List<string> filenames)
    {
        _fileNames = filenames;
    }
    public List<string> GetExcelFiles(string dir, List<string> filenames = null)
    {

        string dirName = dir;
        var dirNames = new List<string>();
        if (filenames != null)
        {
            _fileNames.Concat(filenames);
        }
        try
        {
            foreach (string f in Directory.GetFiles(dirName))
            {
                if (f.ToLower().EndsWith(".xls") || f.ToLower().EndsWith(".xlsx"))
                {
                    _fileNames.Add(f);
                }
            }
            dirNames = Directory.GetDirectories(dirName).ToList();
            foreach (string d in dirNames)
            {
                GetExcelFiles(d, _fileNames);
            }
        }
        catch (Exception ex)
        {
            //Bam
        }
        return _fileNames;
    }

A very simple solution, returns a list of files.

    public static List<string> AllFilesInFolder(string folder)
    {
        var result = new List<string>();

        foreach (string f in Directory.GetFiles(folder))
        {
            result.Add(f);
        }

        foreach (string d in Directory.GetDirectories(folder))
        {
            result.AddRange(AllFilesInFolder(d));
        }

        return result;
    }

static void Main(string[] args)
        {
            string[] array1 = Directory.GetFiles(@"D:\");
            string[] array2 = System.IO.Directory.GetDirectories(@"D:\");
            Console.WriteLine("--- Files: ---");
            foreach (string name in array1)
            {
                Console.WriteLine(name);
            }
            foreach (string name in array2)
            {
                Console.WriteLine(name);
            }
                  Console.ReadLine();
        }