RegistryRights Enumeração

Definição

public enum class RegistryRights

[System.Flags]
public enum RegistryRights

[<System.Flags>]
type RegistryRights = 

Public Enum RegistryRights

Herança

Object

ValueType

Enum

RegistryRights

Atributos

FlagsAttribute

Campos

Exemplos

O seguinte exemplo de código demonstra a utilização da RegistryRights enumeração. O código cria uma chave de teste, permitindo ao utilizador atual direitos de acesso ReadKey e Delete, mas negando os direitos de ChangePermissions e WriteKey. As tentativas subsequentes de manipular a chave têm sucesso ou falham dependendo dessas permissões.

Antes de a chave ser apagada, o código pausa. Pode mudar para o Editor do Registo (Regedit.exe ou Regedt32.exe) e verificar se os mesmos direitos de acesso se aplicam quando a chave é acedida usando o Editor do Registo.

Este exemplo funciona melhor se usares o RunAs da linha de comandos para executar o Editor do Registo e o código de exemplo como utilizador local sem direitos de administrador. Por exemplo, se definiu um utilizador local chamado TestUser, o comando runas /user:TestUser cmd abre uma janela de comandos a partir da qual pode executar o Editor do Registo e depois o código de exemplo.

using System;
using System.Reflection;
using System.Security;
using System.Security.AccessControl;
using Microsoft.Win32;

public class Example
{
    public static void Main()
    {
        // Delete the example key if it exists.
        try
        {
            Registry.CurrentUser.DeleteSubKey("RegistryRightsExample");
            Console.WriteLine("Example key has been deleted.");
        }
        catch (ArgumentException)
        {
            // ArgumentException is thrown if the key does not exist. In
            // this case, there is no reason to display a message.
        }
        catch (Exception ex)
        {
            Console.WriteLine("Unable to delete the example key: {0}", ex);
            return;
        }

        string user = Environment.UserDomainName + "\\" + Environment.UserName;

        RegistrySecurity rs = new RegistrySecurity();

        // Allow the current user to read and delete the key.
        //
        rs.AddAccessRule(new RegistryAccessRule(user,
            RegistryRights.ReadKey | RegistryRights.Delete,
            InheritanceFlags.None,
            PropagationFlags.None,
            AccessControlType.Allow));

        // Prevent the current user from writing or changing the
        // permission set of the key. Note that if Delete permission
        // were not allowed in the previous access rule, denying
        // WriteKey permission would prevent the user from deleting the
        // key.
        rs.AddAccessRule(new RegistryAccessRule(user,
            RegistryRights.WriteKey | RegistryRights.ChangePermissions,
            InheritanceFlags.None,
            PropagationFlags.None,
            AccessControlType.Deny));

        // Create the example key with registry security.
        RegistryKey rk = null;
        try
        {
            rk = Registry.CurrentUser.CreateSubKey("RegistryRightsExample",
                RegistryKeyPermissionCheck.Default, rs);
            Console.WriteLine("\r\nExample key created.");
            rk.SetValue("ValueName", "StringValue");
        }
        catch (Exception ex)
        {
            Console.WriteLine("\r\nUnable to create the example key: {0}", ex);
        }
        if (rk != null) rk.Close();

        rk = Registry.CurrentUser;

        RegistryKey rk2;

        // Open the key with read access.
        rk2 = rk.OpenSubKey("RegistryRightsExample", false);
        Console.WriteLine("\r\nRetrieved value: {0}", rk2.GetValue("ValueName"));
        rk2.Close();

        // Attempt to open the key with write access.
        try
        {
            rk2 = rk.OpenSubKey("RegistryRightsExample", true);
        }
        catch (SecurityException ex)
        {
            Console.WriteLine("\nUnable to write to the example key." +
                " Caught SecurityException: {0}", ex.Message);
        }
        if (rk2 != null) rk2.Close();

        // Attempt to change permissions for the key.
        try
        {
            rs = new RegistrySecurity();
            rs.AddAccessRule(new RegistryAccessRule(user,
                RegistryRights.WriteKey,
                InheritanceFlags.None,
                PropagationFlags.None,
                AccessControlType.Allow));
            rk2 = rk.OpenSubKey("RegistryRightsExample", false);
            rk2.SetAccessControl(rs);
            Console.WriteLine("\r\nExample key permissions were changed.");
        }
        catch (UnauthorizedAccessException ex)
        {
            Console.WriteLine("\nUnable to change permissions for the example key." +
                " Caught UnauthorizedAccessException: {0}", ex.Message);
        }
        if (rk2 != null) rk2.Close();

        Console.WriteLine("\r\nPress Enter to delete the example key.");
        Console.ReadLine();

        try
        {
            rk.DeleteSubKey("RegistryRightsExample");
            Console.WriteLine("Example key was deleted.");
        }
        catch(Exception ex)
        {
            Console.WriteLine("Unable to delete the example key: {0}", ex);
        }

        rk.Close();
    }
}

/* This code example produces the following output:

Example key created.

Retrieved value: StringValue

Unable to write to the example key. Caught SecurityException: Requested registry access is not allowed.

Unable to change permissions for the example key. Caught UnauthorizedAccessException: Cannot write to the registry key.

Press Enter to delete the example key.

Example key was deleted.
 */

Imports System.Reflection
Imports System.Security
Imports System.Security.AccessControl
Imports Microsoft.Win32

Public Class Example
    Public Shared Sub Main()
        ' Delete the example key if it exists.
        Try
            Registry.CurrentUser.DeleteSubKey("RegistryRightsExample")
            Console.WriteLine("Example key has been deleted.")
        Catch ex As ArgumentException
            ' ArgumentException is thrown if the key does not exist. In
            ' this case, there is no reason to display a message.
        Catch ex As Exception
            Console.WriteLine("Unable to delete the example key: {0}", ex)
            Return
        End Try

        Dim user As String = Environment.UserDomainName & "\" & Environment.UserName

        Dim rs As New RegistrySecurity()

        ' Allow the current user to read and delete the key.
        '
        rs.AddAccessRule(new RegistryAccessRule(user, _
            RegistryRights.ReadKey Or RegistryRights.Delete, _
            InheritanceFlags.None, _
            PropagationFlags.None, _
            AccessControlType.Allow))

        ' Prevent the current user from writing or changing the
        ' permission set of the key. Note that if Delete permission
        ' were not allowed in the previous access rule, denying
        ' WriteKey permission would prevent the user from deleting the 
        ' key.
        rs.AddAccessRule(new RegistryAccessRule(user, _
            RegistryRights.WriteKey Or RegistryRights.ChangePermissions, _
            InheritanceFlags.None, _
            PropagationFlags.None, _
            AccessControlType.Deny))

        ' Create the example key with registry security.
        Dim rk As RegistryKey = Nothing
        Try
            rk = Registry.CurrentUser.CreateSubKey("RegistryRightsExample", _
                RegistryKeyPermissionCheck.Default, rs)
            Console.WriteLine(vbCrLf & "Example key created.")
            rk.SetValue("ValueName", "StringValue")
        Catch ex As Exception
            Console.WriteLine(vbCrLf & "Unable to create the example key: {0}", ex)
        End Try

        If rk IsNot Nothing Then rk.Close()

        rk = Registry.CurrentUser

        Dim rk2 As RegistryKey
        
        ' Open the key with read access.
        rk2 = rk.OpenSubKey("RegistryRightsExample", False)
        Console.WriteLine(vbCrLf & "Retrieved value: {0}", rk2.GetValue("ValueName"))
        rk2.Close()

        ' Attempt to open the key with write access.
        Try
            rk2 = rk.OpenSubKey("RegistryRightsExample", True)
        Catch ex As SecurityException
            Console.WriteLine(vbCrLf & "Unable to write to the example key." _
                & " Caught SecurityException: {0}", ex.Message)
        End Try
        If rk2 IsNot Nothing Then rk2.Close()

        ' Attempt to change permissions for the key.
        Try
            rs = New RegistrySecurity()
            rs.AddAccessRule(new RegistryAccessRule(user, _
                RegistryRights.WriteKey, _
                InheritanceFlags.None, _
                PropagationFlags.None, _
                AccessControlType.Allow))
            rk2 = rk.OpenSubKey("RegistryRightsExample", False)
            rk2.SetAccessControl(rs)
            Console.WriteLine(vbCrLf & "Example key permissions were changed.")
        Catch ex As UnauthorizedAccessException
            Console.WriteLine(vbCrLf & "Unable to change permissions for the example key." _
                & " Caught UnauthorizedAccessException: {0}", ex.Message)
        End Try
        If rk2 IsNot Nothing Then rk2.Close()

        Console.WriteLine(vbCrLf & "Press Enter to delete the example key.")
        Console.ReadLine()

        Try
            rk.DeleteSubKey("RegistryRightsExample")
            Console.WriteLine("Example key was deleted.")
        Catch ex As Exception
            Console.WriteLine("Unable to delete the example key: {0}", ex)
        End Try

        rk.Close()
    End Sub
End Class

' This code produces the following output:
'
'Example key created.
'
'Retrieved value: StringValue
'
'Unable to write to the example key. Caught SecurityException: Requested registry access is not allowed.
'
'Unable to change permissions for the example key. Caught UnauthorizedAccessException: Cannot write to the registry key.
'
'Press Enter to delete the example key.
'
'Example key was deleted.

Observações

Use a RegistryRights enumeração para especificar direitos de acesso ao registo quando criar RegistrySecurity objetos. Para aplicar direitos de acesso a uma chave de registo, primeiro adiciona RegistryAccessRule objetos a um RegistrySecurity objeto, depois anexa o RegistrySecurity objeto à chave usando o RegistryKey.SetAccessControl método, ou uma sobrecarga apropriada do RegistryKey.CreateSubKey método.

Ver também

• RegistryAccessRule
• RegistrySecurity
• RegistryAuditRule