List all files and directories in a directory + subdirectories

Question

I want to list every file and directory contained in a directory and subdirectories of that directory. If I chose C:\\ as the directory, the program would get every name of

Answer 1

The following example the fastest (not parallelized) way list files and sub-folders in a directory tree handling exceptions. It would be faster to use Directory.EnumerateDirectories using SearchOption.AllDirectories to enumerate all directories, but this method will fail if hits a UnauthorizedAccessException or PathTooLongException.

Uses the generic Stack collection type, which is a last in first out (LIFO) stack and does not use recursion. From https://msdn.microsoft.com/en-us/library/bb513869.aspx, allows you to enumerate all sub-directories and files and deal effectively with those exceptions.

    public class StackBasedIteration
{
    static void Main(string[] args)
    {
        // Specify the starting folder on the command line, or in 
        // Visual Studio in the Project > Properties > Debug pane.
        TraverseTree(args[0]);

        Console.WriteLine("Press any key");
        Console.ReadKey();
    }

    public static void TraverseTree(string root)
    {
        // Data structure to hold names of subfolders to be
        // examined for files.
        Stack<string> dirs = new Stack<string>(20);

        if (!System.IO.Directory.Exists(root))
        {
            throw new ArgumentException();
        }
        dirs.Push(root);

        while (dirs.Count > 0)
        {
            string currentDir = dirs.Pop();
            string[] subDirs;
            try
            {
                subDirs = System.IO.Directory.EnumerateDirectories(currentDir); //TopDirectoryOnly
            }
            // An UnauthorizedAccessException exception will be thrown if we do not have
            // discovery permission on a folder or file. It may or may not be acceptable 
            // to ignore the exception and continue enumerating the remaining files and 
            // folders. It is also possible (but unlikely) that a DirectoryNotFound exception 
            // will be raised. This will happen if currentDir has been deleted by
            // another application or thread after our call to Directory.Exists. The 
            // choice of which exceptions to catch depends entirely on the specific task 
            // you are intending to perform and also on how much you know with certainty 
            // about the systems on which this code will run.
            catch (UnauthorizedAccessException e)
            {                    
                Console.WriteLine(e.Message);
                continue;
            }
            catch (System.IO.DirectoryNotFoundException e)
            {
                Console.WriteLine(e.Message);
                continue;
            }

            string[] files = null;
            try
            {
                files = System.IO.Directory.EnumerateFiles(currentDir);
            }

            catch (UnauthorizedAccessException e)
            {

                Console.WriteLine(e.Message);
                continue;
            }

            catch (System.IO.DirectoryNotFoundException e)
            {
                Console.WriteLine(e.Message);
                continue;
            }
            // Perform the required action on each file here.
            // Modify this block to perform your required task.
            foreach (string file in files)
            {
                try
                {
                    // Perform whatever action is required in your scenario.
                    System.IO.FileInfo fi = new System.IO.FileInfo(file);
                    Console.WriteLine("{0}: {1}, {2}", fi.Name, fi.Length, fi.CreationTime);
                }
                catch (System.IO.FileNotFoundException e)
                {
                    // If file was deleted by a separate application
                    //  or thread since the call to TraverseTree()
                    // then just continue.
                    Console.WriteLine(e.Message);
                    continue;
                }
                catch (UnauthorizedAccessException e)
                {                    
                    Console.WriteLine(e.Message);
                    continue;
                }
            }

            // Push the subdirectories onto the stack for traversal.
            // This could also be done before handing the files.
            foreach (string str in subDirs)
                dirs.Push(str);
        }
    }
}

Answer 2

If you don't have access to a subfolder inside the directory tree, Directory.GetFiles stops and throws the exception resulting in a null value in the receiving string[].

Here, see this answer https://stackoverflow.com/a/38959208/6310707

It manages the exception inside the loop and keep on working untill the entire folder is traversed.

Answer 3

Create List Of String

    public static List<string> HTMLFiles = new List<string>();

 private void Form1_Load(object sender, EventArgs e)
        {

     HTMLFiles.AddRange(Directory.GetFiles(@"C:\DataBase", "*.txt"));
            foreach (var item in HTMLFiles)
            {
                MessageBox.Show(item);
            }

}

Answer 4

public static void DirectorySearch(string dir)
{
    try
    {
        foreach (string f in Directory.GetFiles(dir))
        {
            Console.WriteLine(Path.GetFileName(f));
        }
        foreach (string d in Directory.GetDirectories(dir))
        {
            Console.WriteLine(Path.GetFileName(d));
            DirectorySearch(d);
        }
    }
    catch (System.Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
}

Note: the function shows only names without relative paths.

Answer 5

Use the GetDirectories and GetFiles methods to get the folders and files.

Use the SearchOption AllDirectories to get the folders and files in the subfolders also.

Answer 6

the logical and ordered way:

using System;
using System.Collections.Generic;
using System.IO;
using System.Reflection;

namespace DirLister
{
class Program
{
    public static void Main(string[] args)
    {
        //with reflection I get the directory from where this program is running, thus listing all files from there and all subdirectories
        string[] st = FindFileDir(Path.GetDirectoryName(Assembly.GetEntryAssembly().Location));
        using ( StreamWriter sw = new StreamWriter("listing.txt", false ) )
        {
            foreach(string s in st)
            {
                //I write what I found in a text file
                sw.WriteLine(s);
            }
        }
    }

    private static string[] FindFileDir(string beginpath)
    {
        List<string> findlist = new List<string>();

        /* I begin a recursion, following the order:
         * - Insert all the files in the current directory with the recursion
         * - Insert all subdirectories in the list and rebegin the recursion from there until the end
         */
        RecurseFind( beginpath, findlist );

        return findlist.ToArray();
    }

    private static void RecurseFind( string path, List<string> list )
    {
        string[] fl = Directory.GetFiles(path);
        string[] dl = Directory.GetDirectories(path);
        if ( fl.Length>0 || dl.Length>0 )
        {
            //I begin with the files, and store all of them in the list
            foreach(string s in fl)
                list.Add(s);
            //I then add the directory and recurse that directory, the process will repeat until there are no more files and directories to recurse
            foreach(string s in dl)
            {
                list.Add(s);
                RecurseFind(s, list);
            }
        }
    }
}
}