EventWaitHandleSecurity.RemoveAccessRuleSpecific Método
Definição
Importante
Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.
Procura uma regra de controlo de acesso que corresponda exatamente à regra especificada e, se encontrada, remove-a.
public:
void RemoveAccessRuleSpecific(System::Security::AccessControl::EventWaitHandleAccessRule ^ rule);
public void RemoveAccessRuleSpecific(System.Security.AccessControl.EventWaitHandleAccessRule rule);
override this.RemoveAccessRuleSpecific : System.Security.AccessControl.EventWaitHandleAccessRule -> unit
Public Sub RemoveAccessRuleSpecific (rule As EventWaitHandleAccessRule)
Parâmetros
O EventWaitHandleAccessRule para remover.
Exceções
rule é null.
Exemplos
O seguinte exemplo de código mostra que o RemoveAccessRuleSpecific método requer uma correspondência exata para remover uma regra, e que as regras para permitir e negar direitos são independentes uma da outra.
O exemplo cria um EventWaitHandleSecurity objeto, adiciona regras que permitem e negam vários direitos ao utilizador atual, e depois funde direitos adicionais na regra de Allow acesso. O exemplo passa então a regra original Allow ao RemoveAccessRuleSpecific método e mostra os resultados, mostrando que nada é eliminado. O exemplo constrói então uma regra que corresponde à Allow regra no EventWaitHandleSecurity objeto e utiliza com sucesso o RemoveAccessRuleSpecific método para remover a regra.
Note
Este exemplo não associa o objeto de segurança a um EventWaitHandle objeto. Exemplos que anexam objetos de segurança podem ser encontrados em EventWaitHandle.GetAccessControl e EventWaitHandle.SetAccessControl.
using System;
using System.Threading;
using System.Security.AccessControl;
using System.Security.Principal;
public class Example
{
public static void Main()
{
// Create a string representing the current user.
string user = Environment.UserDomainName + "\\" +
Environment.UserName;
// Create a security object that grants no access.
EventWaitHandleSecurity mSec = new EventWaitHandleSecurity();
// Add a rule that grants the current user the
// right to wait on or signal the event.
EventWaitHandleAccessRule ruleA = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify,
AccessControlType.Allow);
mSec.AddAccessRule(ruleA);
// Add a rule that denies the current user the
// right to change permissions on the event.
EventWaitHandleAccessRule rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.ChangePermissions,
AccessControlType.Deny);
mSec.AddAccessRule(rule);
// Display the rules in the security object.
ShowSecurity(mSec);
// Add a rule that allows the current user the
// right to read permissions on the event. This rule
// is merged with the existing Allow rule.
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.ReadPermissions,
AccessControlType.Allow);
mSec.AddAccessRule(rule);
ShowSecurity(mSec);
// Attempt to remove the original rule (granting
// the right to wait on or signal the event) with
// RemoveAccessRuleSpecific. The removal fails,
// because the right to read the permissions on the
// event has been added to the rule, so that it no
// longer matches the original rule.
Console.WriteLine("Attempt to use RemoveAccessRuleSpecific on the original rule.");
mSec.RemoveAccessRuleSpecific(ruleA);
ShowSecurity(mSec);
// Create a rule that grants the current user
// the right to wait on or signal the event, and
// to read permissions. Use this rule to remove
// the Allow rule for the current user.
Console.WriteLine("Use RemoveAccessRuleSpecific with the correct rights.");
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify |
EventWaitHandleRights.ReadPermissions,
AccessControlType.Allow);
mSec.RemoveAccessRuleSpecific(rule);
ShowSecurity(mSec);
}
private static void ShowSecurity(EventWaitHandleSecurity security)
{
Console.WriteLine("\r\nCurrent access rules:\r\n");
foreach(EventWaitHandleAccessRule ar in
security.GetAccessRules(true, true, typeof(NTAccount)))
{
Console.WriteLine(" User: {0}", ar.IdentityReference);
Console.WriteLine(" Type: {0}", ar.AccessControlType);
Console.WriteLine(" Rights: {0}", ar.EventWaitHandleRights);
Console.WriteLine();
}
}
}
/*This code example produces output similar to following:
Current access rules:
User: TestDomain\TestUser
Type: Deny
Rights: ChangePermissions
User: TestDomain\TestUser
Type: Allow
Rights: Modify, Synchronize
Current access rules:
User: TestDomain\TestUser
Type: Deny
Rights: ChangePermissions
User: TestDomain\TestUser
Type: Allow
Rights: Modify, ReadPermissions, Synchronize
Attempt to use RemoveAccessRuleSpecific on the original rule.
Current access rules:
User: TestDomain\TestUser
Type: Deny
Rights: ChangePermissions
User: TestDomain\TestUser
Type: Allow
Rights: Modify, ReadPermissions, Synchronize
Use RemoveAccessRuleSpecific with the correct rights.
Current access rules:
User: TestDomain\TestUser
Type: Deny
Rights: ChangePermissions
*/
Imports System.Threading
Imports System.Security.AccessControl
Imports System.Security.Principal
Public Class Example
Public Shared Sub Main()
' Create a string representing the current user.
Dim user As String = Environment.UserDomainName _
& "\" & Environment.UserName
' Create a security object that grants no access.
Dim mSec As New EventWaitHandleSecurity()
' Add a rule that grants the current user the
' right to wait on or signal the event.
Dim ruleA As New EventWaitHandleAccessRule(user, _
EventWaitHandleRights.Synchronize _
Or EventWaitHandleRights.Modify, _
AccessControlType.Allow)
mSec.AddAccessRule(ruleA)
' Add a rule that denies the current user the
' right to change permissions on the event.
Dim rule As New EventWaitHandleAccessRule(user, _
EventWaitHandleRights.ChangePermissions, _
AccessControlType.Deny)
mSec.AddAccessRule(rule)
' Display the rules in the security object.
ShowSecurity(mSec)
' Add a rule that allows the current user the
' right to read permissions on the event. This rule
' is merged with the existing Allow rule.
rule = New EventWaitHandleAccessRule(user, _
EventWaitHandleRights.ReadPermissions, _
AccessControlType.Allow)
mSec.AddAccessRule(rule)
ShowSecurity(mSec)
' Attempt to remove the original rule (granting
' the right to wait on or signal the event) with
' RemoveAccessRuleSpecific. The removal fails,
' because the right to read the permissions on the
' event has been added to the rule, so that it no
' longer matches the original rule.
Console.WriteLine("Attempt to use RemoveAccessRuleSpecific on the original rule.")
mSec.RemoveAccessRuleSpecific(ruleA)
ShowSecurity(mSec)
' Create a rule that grants the current user
' the right to wait on or signal the event, and
' to read permissions. Use this rule to remove
' the Allow rule for the current user.
Console.WriteLine("Use RemoveAccessRuleSpecific with the correct rights.")
rule = New EventWaitHandleAccessRule(user, _
EventWaitHandleRights.Synchronize _
Or EventWaitHandleRights.Modify _
Or EventWaitHandleRights.ReadPermissions, _
AccessControlType.Allow)
mSec.RemoveAccessRuleSpecific(rule)
ShowSecurity(mSec)
End Sub
Private Shared Sub ShowSecurity(ByVal security As EventWaitHandleSecurity)
Console.WriteLine(vbCrLf & "Current access rules:" & vbCrLf)
For Each ar As EventWaitHandleAccessRule In _
security.GetAccessRules(True, True, GetType(NTAccount))
Console.WriteLine(" User: {0}", ar.IdentityReference)
Console.WriteLine(" Type: {0}", ar.AccessControlType)
Console.WriteLine(" Rights: {0}", ar.EventWaitHandleRights)
Console.WriteLine()
Next
End Sub
End Class
'This code example produces output similar to following:
'
'Current access rules:
'
' User: TestDomain\TestUser
' Type: Deny
' Rights: ChangePermissions
'
' User: TestDomain\TestUser
' Type: Allow
' Rights: Modify, Synchronize
'
'
'Current access rules:
'
' User: TestDomain\TestUser
' Type: Deny
' Rights: ChangePermissions
'
' User: TestDomain\TestUser
' Type: Allow
' Rights: Modify, ReadPermissions, Synchronize
'
'Attempt to use RemoveAccessRuleSpecific on the original rule.
'
'Current access rules:
'
' User: TestDomain\TestUser
' Type: Deny
' Rights: ChangePermissions
'
' User: TestDomain\TestUser
' Type: Allow
' Rights: Modify, ReadPermissions, Synchronize
'
'Use RemoveAccessRuleSpecific with the correct rights.
'
'Current access rules:
'
' User: TestDomain\TestUser
' Type: Deny
' Rights: ChangePermissions
Observações
A regra só é removida se corresponder rule exatamente a todos os detalhes, incluindo as bandeiras. Outras regras com o mesmo utilizador não AccessControlType são afetadas.
Importante
Uma regra representa uma ou mais entradas subjacentes de controlo de acesso (ACE), e estas entradas são divididas ou combinadas conforme necessário quando se modificam as regras de segurança de acesso para um utilizador. Assim, uma regra pode deixar de existir na forma específica que tinha quando foi adicionada e, nesse caso, o RemoveAccessRuleSpecific método não pode removê-la.