File and Directory Classes in C#

What are File and Directory Classes in C#?

The **File** and **Directory** classes in C# provide methods for performing operations on files and directories, such as **creating, deleting, copying, moving, and checking existence**. These classes are part of the **System.IO** namespace.

Key Features of File & Directory Classes

Provide static methods for handling **files and folders**.
Support operations like **creating, deleting, moving, and checking existence**.
Can retrieve **file attributes, sizes, and timestamps**.
Work seamlessly with **file paths and directories**.

Working with the File Class

The **File** class provides static methods for handling file operations.

Example: Creating, Writing, and Reading a File

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string filePath = "testfile.txt";

        // Creating and writing to the file
        File.WriteAllText(filePath, "Hello, File Class!");

        // Checking if file exists
        if (File.Exists(filePath))
        {
            Console.WriteLine("File created successfully.");

            // Reading file content
            string content = File.ReadAllText(filePath);
            Console.WriteLine($"File Content: {content}");
        }
    }
}

// Output:
// File created successfully.
// File Content: Hello, File Class!

The **File.WriteAllText()** and **File.ReadAllText()** methods make file operations easy.

Copying, Moving, and Deleting Files

The **File** class allows copying, moving, and deleting files.

Example: Copying, Moving, and Deleting a File

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string sourceFile = "testfile.txt";
        string copyFile = "copyfile.txt";
        string movedFile = "movedfile.txt";

        // Copy File
        File.Copy(sourceFile, copyFile, true);
        Console.WriteLine("File copied successfully.");

        // Move File
        File.Move(copyFile, movedFile);
        Console.WriteLine("File moved successfully.");

        // Delete File
        File.Delete(movedFile);
        Console.WriteLine("File deleted successfully.");
    }
}

// Output:
// File copied successfully.
// File moved successfully.
// File deleted successfully.

The **File.Copy()**, **File.Move()**, and **File.Delete()** methods simplify file management.

Working with the Directory Class

The **Directory** class provides static methods to manage directories.

Example: Creating, Checking, and Deleting a Directory

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string directoryPath = "MyDirectory";

        // Create Directory
        if (!Directory.Exists(directoryPath))
        {
            Directory.CreateDirectory(directoryPath);
            Console.WriteLine("Directory created successfully.");
        }

        // Check if Directory Exists
        if (Directory.Exists(directoryPath))
        {
            Console.WriteLine("Directory exists.");
        }

        // Delete Directory
        Directory.Delete(directoryPath);
        Console.WriteLine("Directory deleted successfully.");
    }
}

// Output:
// Directory created successfully.
// Directory exists.
// Directory deleted successfully.

The **Directory.CreateDirectory()**, **Directory.Exists()**, and **Directory.Delete()** methods handle directory operations.

Listing Files and Directories

You can retrieve files and directories inside a folder using **Directory.GetFiles()** and **Directory.GetDirectories()**.

Example: Listing Files and Directories

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string directoryPath = "."; // Current directory

        // Get all files in the directory
        string[] files = Directory.GetFiles(directoryPath);
        Console.WriteLine("Files in Directory:");
        foreach (var file in files)
        {
            Console.WriteLine(file);
        }

        // Get all subdirectories
        string[] directories = Directory.GetDirectories(directoryPath);
        Console.WriteLine("\nSubdirectories:");
        foreach (var dir in directories)
        {
            Console.WriteLine(dir);
        }
    }
}

// Output (depends on system files):
// Files in Directory:
// testfile.txt
// movedfile.txt

// Subdirectories:
// MyDirectory
// AnotherFolder

The **Directory.GetFiles()** method lists all files, while **Directory.GetDirectories()** lists subdirectories.

Best Practices for Using File & Directory Classes

Use **File.Exists()** and **Directory.Exists()** before performing operations.
Always **handle exceptions** when dealing with files and directories.
Use **relative paths** instead of absolute paths when possible.
Clean up **unused files and directories** to prevent clutter.

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