FileSystemSecurity.AddAccessRule(FileSystemAccessRule) Method

Reference

Definition

Namespace:: System.Security.AccessControl

Assembly:: System.IO.FileSystem.AccessControl.dll

Assembly:: mscorlib.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Adds the specified access control list (ACL) permission to the current file or directory.

public:
 void AddAccessRule(System::Security::AccessControl::FileSystemAccessRule ^ rule);

public void AddAccessRule (System.Security.AccessControl.FileSystemAccessRule rule);

override this.AddAccessRule : System.Security.AccessControl.FileSystemAccessRule -> unit

Public Sub AddAccessRule (rule As FileSystemAccessRule)

Parameters

rule: FileSystemAccessRule

A FileSystemAccessRule object that represents an access control list (ACL) permission to add to a file or directory.

Exceptions

ArgumentNullException

The rule parameter is null.

Examples

The following code example uses the FileSecurity class to add and then remove an access control list (ACL) entry from a file. You must supply a valid user or group account to run this example.

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 from 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);
    }
}

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);

            // Remove the FileSystemAccessRule from the security settings.
            fSecurity.RemoveAccessRule(new FileSystemAccessRule(account,
                rights, controlType));

            // Set the new access settings.
            File.SetAccessControl(fileName, fSecurity);
        }
    }
}

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)

        ' Remove the FileSystemAccessRule from the security settings. 
        fSecurity.RemoveAccessRule(New FileSystemAccessRule(account, _
            rights, controlType))

        ' Set the new access settings.
        File.SetAccessControl(fileName, fSecurity)

    End Sub
End Module

Remarks

The AddAccessRule method adds a new rule to the list of rules contained within a FileSystemSecurity object.

If an access control list (ACL) already exists for the specified rule, the AddAccessRule method will still add the rule, with one exception: a FileSystemAccessRule object created using the Deny enumeration value supersedes an object created using the Allow enumeration value.

To persist new or changed ACL information to a file, use the SetAccessControl or SetAccessControl method. To persist new or changed ACL information to a directory, use the SetAccessControl or SetAccessControl method.

To retrieve ACL information from a file, use the GetAccessControl or GetAccessControl method. To retrieve ACL information from a directory, use the GetAccessControl or GetAccessControl method.

When you add an access rule without setting the Synchronize flag, the Synchronize flag will be automatically added to your rule. If you remove the rule later without specifying the Synchronize flag, the flag will automatically be removed.

Applies to