File.GetAccessControl Method (String)

 
System_CAPS_noteNote

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Gets a FileSecurity object that encapsulates the access control list (ACL) entries for a specified file.

Namespace:   System.IO
Assembly:  mscorlib (in mscorlib.dll)

Public Shared Function GetAccessControl (
	path As String
) As FileSecurity

Parameters

path
Type: System.String

The path to a file containing a FileSecurity object that describes the file's access control list (ACL) information.

Return Value

Type: System.Security.AccessControl.FileSecurity

A FileSecurity object that encapsulates the access control rules for the file described by the path parameter.

Exception Condition
IOException

An I/O error occurred while opening the file.

SEHException

The path parameter is null.

SystemException

The file could not be found.

UnauthorizedAccessException

The path parameter specified a file that is read-only.

-or-

This operation is not supported on the current platform.

-or-

The path parameter specified a directory.

-or-

The caller does not have the required permission.

Use the GetAccessControl method to retrieve the access control list (ACL) entries for a file.

An ACL describes individuals and/or groups who have, or do not have, rights to specific actions on the given file. For more information, see How to: Add or Remove Access Control List Entries.

In NTFS environments, ReadAttributes and ReadExtendedAttributes are granted to the user if the user has ListDirectory rights on the parent folder. To deny ReadAttributes and ReadExtendedAttributes, deny ListDirectory on the parent directory.

The following code example uses the GetAccessControl and the SetAccessControl methods 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.

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)

        ' 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

FileIOPermission

for permission to read the access control list. Security action: Demand. Associated enumerations: FileIOPermissionAccess.NoAccess, AccessControlActions.View

.NET Framework
Available since 2.0
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