C# Tutorial For Beginners: Working with File System Objects
Updated: Jan 19, 2022
This article will review the System.IO namespaces and its main classes that we can use to work with file system objects.
The Directory Class
This class contains static methods for Directories manipulation; the table below includes the main methods you can use while working with this class:
Code Examples
class Program
{
static void Main(string[] args)
{
//Example 1: Delete a specific folder
Directory.Delete("C:\\Folder 1\\Folder 2");
//OR
Directory.Delete("C:\\Folder 1\\Folder 2", true);//In case that folder has files
//Example 2: Creating two folders, “Folder 1” and an inner folder, “Folder 2.”
Directory.CreateDirectory("C:\\Folder 1\\Folder 2");
//Example 3: Get list of files in a given folder
string[] FilesInFolder = Directory.GetFiles("C:\\Folder 1");
foreach (var file in FilesInFolder)
{
Console.WriteLine(file); //Will print list of files under folder "Example 1"
}
//Example 4: Get a folder list under specific path
string[] ArrayOfDirectories = Directory.GetDirectories("c:\\");
foreach (var item in ArrayOfDirectories)
{
Console.WriteLine(item);
}
//Example 5: Getting the folder creation time
DateTime FolderCreation2 = Directory.GetCreationTime("c:\\Folder 1");
//Example 6: Getting the parent folder of a specific path
Directory.GetParent("c:\\Folder 1\\Folder 2"); //Will return "Folder 1"
//Example 7: Get logical Drives
string[] LogicalDrives = Directory.GetLogicalDrives();
foreach (var item in LogicalDrives)
{
Console.WriteLine(item);
}
//Example 8: Check for folder existence under a specific path
if (Directory.Exists("C:\\Folder 1") == true)
{
Console.WriteLine("Directory Exists");
}
else
{
Console.WriteLine("Directory Not Exists");
}
//Example 9: Move a folder to a different location
Directory.Move("c:\\Folder 1\\Folder 2", "c:\\Folder 2");// Wiil MOVE folder 2 under C: drive
}
}
The DirectoryInfo Class
This table contains the main methods you can use while working with this class.
Code Examples
class Program
{
static void Main(string[] args)
{
DirectoryInfo DirectoryInfoInstance = new DirectoryInfo("c:\\Code\\Code");
//Example 1: Create the "Code" folder under C root
DirectoryInfoInstance.Create();
//Example 2: Getting the parent folder of the instance
Console.WriteLine(DirectoryInfoInstance.Parent);//Will return "Code"
//Example 3: Validate Folder existence
if (DirectoryInfoInstance.Exists == true)
{
Console.WriteLine("Folder exist");
}
else
{
Console.WriteLine("Folder Not exist");
}
//Example 4: Getting the Folder creation time
Console.WriteLine(DirectoryInfoInstance.CreationTime);
//Example 5: Getting instance name
Console.WriteLine(DirectoryInfoInstance.Name);
//Example 6: Getting the full path of the instance
Console.WriteLine(DirectoryInfoInstance.FullName);
//Example 7: Getting the root partition of the instance
Console.WriteLine(DirectoryInfoInstance.Root);
//Example 8: Getting the root partition of the instance
Console.WriteLine(DirectoryInfoInstance.Attributes);
}
}
The File Class
Code Examples
static void Main(string[] args)
{
Directory.CreateDirectory("C:\\Working With Files");
//File Creation options:
//Example 1: Create three new files under specific path
for (int i = 0; i < 3; i++)
{
File.Create("C:\\Working With Files\\File_" + i + ".txt");
}
//Example 2: Create a file with Encryption
File.Create("C:\\Working With Files\\FileWithACLS.txt",1024,FileOptions.Encrypted);
//Example 3: Create a file with specific ACL's
FileSecurity FileSecuority = new FileSecurity();
FileSecuority.AddAccessRule(new FileSystemAccessRule(@"Everyone", FileSystemRights.FullControl, AccessControlType.Allow));
File.Create("File_0.txt", 333, FileOptions.Asynchronous, FileSecuority);
//Example 4: Add a new ACL to a file
FileSecurity AddAcl = new FileSecurity();
AddAcl.AddAccessRule(new FileSystemAccessRule(@"Administrator", FileSystemRights.Read, AccessControlType.Deny));
File.SetAccessControl("File_0.txt", AddAcl);
//Example 5: Adding permission to a user
FileSecurity AddAcl2 = new FileSecurity();
AddAcl.AddAccessRule(new FileSystemAccessRule(@"Administrator", FileSystemRights.FullControl, AccessControlType.Allow));
File.SetAccessControl("c:\\File_0.txt", AddAcl2);
//Example 6: Remove an ACL from a file
FileSecurity RemoveAcl = new FileSecurity();
AddAcl.RemoveAccessRule(new FileSystemAccessRule(@"Administrator", FileSystemRights.FullControl, AccessControlType.Allow));
File.SetAccessControl("c:\\File_0.txt", RemoveAcl);
//---------------------------
//Example 1: File Copy (True = Overwrite if existing )
File.Copy("c:\\Source file.txt", "D:\\Destination", true);
//Example 2: File Delete
File.Delete("c:\\File_0.txt");
//Example 3: Check if a file exists (return True OR False)
File.Exists("c:\\File_0.txt");
//Example 4: File Move (“Cut-> Paste”)
File.Move("c:\\1.txt", "c:\\1\\1.txt");//Moving the file with the same name
File.Move("c:\\1.txt", "c:\\NewName.txt");//Moving the file and change its name
//Example 5: File Information
DateTime FileCreationDate = File.GetCreationTime("c:\\File_0.txt");
DateTime FileLastAccess = File.GetLastAccessTime("c:\\File_0.txt");
DateTime FileLastWriteTime = File.GetLastWriteTime("c:\\File_0.txt");
Console.WriteLine(@"The file created on : {0}
The file last accessed in : {1}
The last modification on file : {2}"
, FileCreationDate, FileLastAccess, FileLastWriteTime);
}
}
Additional methods which we can use to work with file content:
Code Examples
class Program
{
static void Main(string[] args)
{
//Example 1: Append new lines to a file
string[] text = { "Line1", "Line2", "Line3" };
File.AppendAllLines("c:\\File1.txt", text, Encoding.UTF8);
//Or
File.AppendAllLines("c:\\NewFile.txt", new string[] { "1", "2" }, Encoding.Default);
//Example 2: Read all lines from a file (ReadAllLines) and add them to a string array
string[] FileLines = File.ReadAllLines("c:\\File1.txt", Encoding.UTF8);
foreach (var LineInFile in FileLines)
{
Console.WriteLine(LineInFile);
}
//Example 3: Read all text from a file (ReadAllLines) and add them to a single string
string FileContent = File.ReadAllText("c:\\File1.txt", Encoding.UTF8);
Console.WriteLine(FileContent);
}