#Comprehensive Guide to Managing Files and Directories in C

Managing files and directories is a common task in many applications. In C#, the System.IO namespace provides powerful classes to handle these tasks efficiently. This article covers various aspects of file and directory management with simple and clear C# examples using top-level statements introduced in C# 6 and later.

Get List of Files in Directory and Subdirectories in C#

To retrieve all files in a directory and its subdirectories, use the Directory.GetFiles method with the SearchOption.AllDirectories option.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string[] allFiles = Directory.GetFiles(directoryPath, "*.*", SearchOption.AllDirectories);

foreach (var file in allFiles)
{
    Console.WriteLine(file);
}

Get List of Files in Directory with Extension in C# 

If you need to list files with a specific extension, you can specify the extension in the search pattern.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string extension = "*.txt";
string[] filesWithExtension = Directory.GetFiles(directoryPath, extension);

foreach (var file in filesWithExtension)
{
    Console.WriteLine(file);
}

Directory.GetFiles Search Pattern

The Directory.GetFiles method supports search patterns to filter files based on name, extension, or other criteria.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string searchPattern = "*.jpg";
string[] files = Directory.GetFiles(directoryPath, searchPattern);

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

Find File by Name

To find a specific file by name, you can use Directory.GetFiles with a search pattern.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string fileName = "example.txt";
string[] files = Directory.GetFiles(directoryPath, fileName);

if (files.Length > 0)
{
    Console.WriteLine("File found: " + files[0]);
}
else
{
    Console.WriteLine("File not found.");
}

Get Directory from Path

To get the directory from a file path, you can use Path.GetDirectoryName.

Example:

using System;
using System.IO;

string filePath = @"C:\ExampleDirectory\example.txt";
string directory = Path.GetDirectoryName(filePath);

Console.WriteLine("Directory: " + directory);

Directory GetFiles Search Pattern FileName

If you need to search for files matching a specific filename pattern, use Directory.GetFiles with the pattern.

:Example

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string searchPattern = "file*.txt";
string[] files = Directory.GetFiles(directoryPath, searchPattern);

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

Folder Copy All Files in C# 

To copy all files from one folder to another, you can use File.Copy in a loop.

Example:

using System;
using System.IO;

string sourceDirectory = @"C:\SourceDirectory";
string destinationDirectory = @"C:\DestinationDirectory";

foreach (var file in Directory.GetFiles(sourceDirectory))
{
    string fileName = Path.GetFileName(file);
    string destFile = Path.Combine(destinationDirectory, fileName);
    File.Copy(file, destFile, true); // true to overwrite existing files
}

List Folders in Directory

To list all folders in a directory, use Directory.GetDirectories.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string[] folders = Directory.GetDirectories(directoryPath);

foreach (var folder in folders)
{
    Console.WriteLine(folder);
}

Open a Folder in C# 

To open a folder in Windows Explorer, you can use the Process class.

Example:

using System;
using System.Diagnostics;

string folderPath = @"C:\ExampleDirectory";
Process.Start("explorer.exe", folderPath);

Get Folders in Directory

Similar to listing folders, Directory.GetDirectories can be used to get folders in a directory.

Example:

using System;
using System.IO;

string directoryPath = @"C:\ExampleDirectory";
string[] folders = Directory.GetDirectories(directoryPath);

foreach (var folder in folders)
{
    Console.WriteLine(folder);
}

Folder Picker in C# 

For a folder picker dialog, you typically use Windows Forms or WPF. Here's a basic example using Windows Forms.

:Example

using System;
using System.Windows.Forms;

class Program
{
    [STAThread]
    static void Main()
    {
        using (var folderDialog = new FolderBrowserDialog())
        {
            if (folderDialog.ShowDialog() == DialogResult.OK)
            {
                Console.WriteLine("Selected folder: " + folderDialog.SelectedPath);
            }
        }
    }
}