How to: Add or Remove Access Control List Entries
To add or remove Access Control List (ACL) entries to or from a file, the FileSecurity or DirectorySecurity object must be obtained from the file or directory, modified, and then applied back to the file or directory.
To add or remove an ACL entry from a File
Call the GetAccessControl method to get a FileSecurity object that contains the current ACL entries of a file.
Add or remove ACL entries from the FileSecurity object returned from step 1.
Pass the FileSecurity object to the SetAccessControl method to apply the changes.
To add or remove an ACL entry from a Directory
Call the GetAccessControl method to get a DirectorySecurity object that contains the current ACL entries of a directory.
Add or remove ACL entries from the DirectorySecurity object returned from step 1.
Pass the DirectorySecurity object to the SetAccessControl method to apply the changes.
Example
Imports System
Imports System.IO
Imports System.Security.AccessControl
Module FileExample
Sub Main()
Try
Dim fileName As String = "test.xml"
Console.WriteLine("Adding access control entry for " & fileName)
' Add the access control entry to the file.
AddFileSecurity(fileName, "DomainName\AccountName", _
FileSystemRights.ReadData, AccessControlType.Allow)
Console.WriteLine("Removing access control entry from " & fileName)
' Remove the access control entry from the file.
RemoveFileSecurity(fileName, "DomainName\AccountName", _
FileSystemRights.ReadData, AccessControlType.Allow)
Console.WriteLine("Done.")
Catch e As Exception
Console.WriteLine(e)
End Try
End Sub
' Adds an ACL entry on the specified file for the specified account.
Sub AddFileSecurity(ByVal fileName As String, ByVal account As String, _
ByVal rights As FileSystemRights, ByVal controlType As AccessControlType)
' Get a FileSecurity object that represents the
' current security settings.
Dim fSecurity As FileSecurity = File.GetAccessControl(fileName)
' Add the FileSystemAccessRule to the security settings.
Dim accessRule As FileSystemAccessRule = _
New FileSystemAccessRule(account, rights, controlType)
fSecurity.AddAccessRule(accessRule)
' Set the new access settings.
File.SetAccessControl(fileName, fSecurity)
End Sub
' Removes an ACL entry on the specified file for the specified account.
Sub RemoveFileSecurity(ByVal fileName As String, ByVal account As String, _
ByVal rights As FileSystemRights, ByVal controlType As AccessControlType)
' Get a FileSecurity object that represents the
' current security settings.
Dim fSecurity As FileSecurity = File.GetAccessControl(fileName)
' Add the FileSystemAccessRule to the security settings.
fSecurity.RemoveAccessRule(New FileSystemAccessRule(account, _
rights, controlType))
' Set the new access settings.
File.SetAccessControl(fileName, fSecurity)
End Sub
End Module
using System;
using System.IO;
using System.Security.AccessControl;
namespace FileSystemExample
{
class FileExample
{
public static void Main()
{
try
{
string fileName = "test.xml";
Console.WriteLine("Adding access control entry for "
+ fileName);
// Add the access control entry to the file.
AddFileSecurity(fileName, @"DomainName\AccountName",
FileSystemRights.ReadData, AccessControlType.Allow);
Console.WriteLine("Removing access control entry from "
+ fileName);
// Remove the access control entry from the file.
RemoveFileSecurity(fileName, @"DomainName\AccountName",
FileSystemRights.ReadData, AccessControlType.Allow);
Console.WriteLine("Done.");
}
catch (Exception e)
{
Console.WriteLine(e);
}
}
// Adds an ACL entry on the specified file for the specified account.
public static void AddFileSecurity(string fileName, string account,
FileSystemRights rights, AccessControlType controlType)
{
// Get a FileSecurity object that represents the
// current security settings.
FileSecurity fSecurity = File.GetAccessControl(fileName);
// Add the FileSystemAccessRule to the security settings.
fSecurity.AddAccessRule(new FileSystemAccessRule(account,
rights, controlType));
// Set the new access settings.
File.SetAccessControl(fileName, fSecurity);
}
// Removes an ACL entry on the specified file for the specified account.
public static void RemoveFileSecurity(string fileName, string account,
FileSystemRights rights, AccessControlType controlType)
{
// Get a FileSecurity object that represents the
// current security settings.
FileSecurity fSecurity = File.GetAccessControl(fileName);
// Add the FileSystemAccessRule to the security settings.
fSecurity.RemoveAccessRule(new FileSystemAccessRule(account,
rights, controlType));
// Set the new access settings.
File.SetAccessControl(fileName, fSecurity);
}
}
}
using namespace System;
using namespace System::IO;
using namespace System::Security::AccessControl;
// Adds an ACL entry on the specified file for the specified account.
void AddFileSecurity(String^ fileName, String^ account,
FileSystemRights rights, AccessControlType controlType)
{
// Get a FileSecurity object that represents the
// current security settings.
FileSecurity^ fSecurity = File::GetAccessControl(fileName);
// Add the FileSystemAccessRule to the security settings.
fSecurity->AddAccessRule(gcnew FileSystemAccessRule
(account,rights, controlType));
// Set the new access settings.
File::SetAccessControl(fileName, fSecurity);
}
// Removes an ACL entry on the specified file for the specified account.
void RemoveFileSecurity(String^ fileName, String^ account,
FileSystemRights rights, AccessControlType controlType)
{
// Get a FileSecurity object that represents the
// current security settings.
FileSecurity^ fSecurity = File::GetAccessControl(fileName);
// Remove the FileSystemAccessRule to the security settings.
fSecurity->RemoveAccessRule(gcnew FileSystemAccessRule
(account,rights, controlType));
// Set the new access settings.
File::SetAccessControl(fileName, fSecurity);
}
int main()
{
try
{
String^ fileName = "test.xml";
Console::WriteLine("Adding access control entry for " + fileName);
// Add the access control entry to the file.
AddFileSecurity(fileName, "MYDOMAIN\\MyAccount",
FileSystemRights::ReadData, AccessControlType::Allow);
Console::WriteLine("Removing access control entry from " + fileName);
// Remove the access control entry from the file.
RemoveFileSecurity(fileName, "MYDOMAIN\\MyAccount",
FileSystemRights::ReadData, AccessControlType::Allow);
Console::WriteLine("Done.");
}
catch (Exception^ ex)
{
Console::WriteLine(ex->Message);
}
}
Compiling the Code
You must supply a valid user or group account to run this example. This example uses a File object; however, the same procedure is used for the FileInfo, Directory, and DirectoryInfo classes.