Lock a Folder in C#

Hi,

Here you will learn how to lock and Unlock folders using C#. This tutorial is of good use if you are planning to create a Folder Locking Software. 


Let's start;


Steps

1.Open Visual Studio -> New Project -> Windows Form Application with name 
   FolderLock.

2.Now add buttons, label, textbox and folderBrowserDialog to your blank form and 
   design it as shown in the below screenshot.

3.Rename the controls as given below; (Click on the buttons & textbox and change the
  Text and Name from the Properties dialog box)

     Text         Name
     Lock    -    btnLock
     Unlock -    btnUnlock
     Browse-    btnBrowse
     textbox1-  txtFilePath

4. Now double click on Browse button and copy the below code;
   
     if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
            {
                txtFilePath.Text = folderBrowserDialog1.SelectedPath;
            }

5. Now double click on Lock button and copy the below code;

 if (txtFilePath.Text.Length > 0)
            {
                try
                {
                    string folderPath = txtFilePath.Text;
                    string adminUserName = Environment.UserName;// getting your adminUserName
                    DirectorySecurity ds = Directory.GetAccessControl(folderPath);
                    FileSystemAccessRule fsa = new FileSystemAccessRule(adminUserName, FileSystemRights.FullControl, AccessControlType.Deny);
                    ds.AddAccessRule(fsa);
                    Directory.SetAccessControl(folderPath, ds);
                    MessageBox.Show("Locked");
                }

                catch
                {
                }
            }

    
6. Also double click on Unlock button and copy the below code;
     
           if (txtFilePath.Text.Length > 0)
            {
                try
                {
                    string folderPath = txtFilePath.Text;
                    string adminUserName = Environment.UserName;// getting your adminUserName
                    DirectorySecurity ds = Directory.GetAccessControl(folderPath);
                    FileSystemAccessRule fsa = new FileSystemAccessRule(adminUserName, FileSystemRights.FullControl, AccessControlType.Deny);
                    ds.RemoveAccessRule(fsa);
                    Directory.SetAccessControl(folderPath, ds);
                    MessageBox.Show("Unlocked");
                }
                catch
                {
                }
            }


7. Now your program code window (Form1.cs) looks like the below one.

Form1.cs

using System;
using System.IO;
using System.Security.AccessControl;
using System.Windows.Forms;

namespace FolderLock
{
    public partial class FolderLock : Form
    {
        public FolderLock()
        {
            InitializeComponent();
        }


        private void btnLock_Click(object sender, EventArgs e)
        {
            if (txtFilePath.Text.Length > 0)
            {
                try
                {
                    string folderPath = txtFilePath.Text;
                    string adminUserName = Environment.UserName;// getting your adminUserName
                    DirectorySecurity ds = Directory.GetAccessControl(folderPath);
                    FileSystemAccessRule fsa = new FileSystemAccessRule(adminUserName, FileSystemRights.FullControl, AccessControlType.Deny);
                    ds.AddAccessRule(fsa);
                    Directory.SetAccessControl(folderPath, ds);
                    MessageBox.Show("Locked");
                }

                catch
                {
                }
            }

        }

        private void btnUnlock_Click(object sender, EventArgs e)
        {
            if (txtFilePath.Text.Length > 0)
            {
                try
                {
                    string folderPath = txtFilePath.Text;
                    string adminUserName = Environment.UserName;// getting your adminUserName
                    DirectorySecurity ds = Directory.GetAccessControl(folderPath);
                    FileSystemAccessRule fsa = new FileSystemAccessRule(adminUserName, FileSystemRights.FullControl, AccessControlType.Deny);
                    ds.RemoveAccessRule(fsa);
                    Directory.SetAccessControl(folderPath, ds);
                    MessageBox.Show("Unlocked");
                }
                catch
                {
                }
            }
        }

        private void btnBrowse_Click(object sender, EventArgs e)
        {
            if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
            {
                txtFilePath.Text = folderBrowserDialog1.SelectedPath;
            }
        }
    }
}

8. Now Run your project and Browse a folder. The folder path will be shown in the
   textbox. Now click on Lock button, the folder will be locked and you will get a message
   ( see the screenshot below). Check if you can open the locked folder, No is it? Now    
   click on Unlock and try again. So you have created a locking software. Enjoy :-)

    Output

Conclusion

If you have got any errors / doubts, feel free to comment it.

See Also

• How to Get IP Address Using C#
• OpenFileDialog in C#
• Digital Clock in C#