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SemaphoreSecurity.RemoveAccessRuleSpecific(SemaphoreAccessRule) Método

Definición

Busca una regla de control de acceso que coincida exactamente con la regla especificada y, si la encuentra, la quita.

public:
 void RemoveAccessRuleSpecific(System::Security::AccessControl::SemaphoreAccessRule ^ rule);
public void RemoveAccessRuleSpecific (System.Security.AccessControl.SemaphoreAccessRule rule);
override this.RemoveAccessRuleSpecific : System.Security.AccessControl.SemaphoreAccessRule -> unit
Public Sub RemoveAccessRuleSpecific (rule As SemaphoreAccessRule)

Parámetros

rule
SemaphoreAccessRule

SemaphoreAccessRule que se va a quitar.

Excepciones

rule es null.

Ejemplos

En el ejemplo de código siguiente se muestra que el RemoveAccessRuleSpecific método requiere una coincidencia exacta para quitar una regla y que las reglas para permitir y denegar derechos son independientes entre sí.

En el ejemplo se crea un SemaphoreSecurity objeto , se agregan reglas que permiten y deniegan varios derechos para el usuario actual y, a continuación, se combinan derechos adicionales en la regla de Allow acceso. A continuación, el ejemplo pasa la regla original Allow al RemoveAccessRuleSpecific método y muestra los resultados, lo que muestra que no se elimina nada. A continuación, el ejemplo crea una regla que coincide con la Allow regla en el SemaphoreSecurity objeto y usa correctamente el RemoveAccessRuleSpecific método para quitar la regla.

Nota

En este ejemplo no se adjunta el objeto de seguridad a un Semaphore objeto . Los ejemplos que asocian objetos de seguridad se pueden encontrar en Semaphore.GetAccessControl y Semaphore.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.
        SemaphoreSecurity mSec = new SemaphoreSecurity();

        // Add a rule that grants the current user the 
        // right to enter or release the semaphore.
        SemaphoreAccessRule ruleA = new SemaphoreAccessRule(user, 
            SemaphoreRights.Synchronize | SemaphoreRights.Modify, 
            AccessControlType.Allow);
        mSec.AddAccessRule(ruleA);

        // Add a rule that denies the current user the 
        // right to change permissions on the semaphore.
        SemaphoreAccessRule rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.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 semaphore. This rule
        // is merged with the existing Allow rule.
        rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        ShowSecurity(mSec);

        // Attempt to remove the original rule (granting
        // the right to enter or release the semaphore) with 
        // RemoveAccessRuleSpecific. The removal fails,
        // because the right to read the permissions on the 
        // semaphore 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 enter or release the semaphore, 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 SemaphoreAccessRule(user, 
            SemaphoreRights.Synchronize | SemaphoreRights.Modify | 
                SemaphoreRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.RemoveAccessRuleSpecific(rule);

        ShowSecurity(mSec);
    }

    private static void ShowSecurity(SemaphoreSecurity security)
    {
        Console.WriteLine("\r\nCurrent access rules:\r\n");

        foreach(SemaphoreAccessRule 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.SemaphoreRights);
            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 SemaphoreSecurity()

        ' Add a rule that grants the current user the 
        ' right to enter or release the semaphore.
        Dim ruleA As New SemaphoreAccessRule(user, _
            SemaphoreRights.Synchronize _
            Or SemaphoreRights.Modify, _
            AccessControlType.Allow)
        mSec.AddAccessRule(ruleA)

        ' Add a rule that denies the current user the 
        ' right to change permissions on the semaphore.
        Dim rule As New SemaphoreAccessRule(user, _
            SemaphoreRights.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 semaphore. This rule
        ' is merged with the existing Allow rule.
        rule = New SemaphoreAccessRule(user, _
            SemaphoreRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ShowSecurity(mSec)

        ' Attempt to remove the original rule (granting
        ' the right to enter or release the semaphore) with 
        ' RemoveAccessRuleSpecific. The removal fails,
        ' because the right to read the permissions on the 
        ' semaphore 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 enter or release the semaphore, 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 SemaphoreAccessRule(user, _
            SemaphoreRights.Synchronize _
            Or SemaphoreRights.Modify _
            Or SemaphoreRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.RemoveAccessRuleSpecific(rule)

        ShowSecurity(mSec)
        
    End Sub 

    Private Shared Sub ShowSecurity(ByVal security As SemaphoreSecurity)
        Console.WriteLine(vbCrLf & "Current access rules:" & vbCrLf)

        For Each ar As SemaphoreAccessRule In _
            security.GetAccessRules(True, True, GetType(NTAccount))

            Console.WriteLine("        User: {0}", ar.IdentityReference)
            Console.WriteLine("        Type: {0}", ar.AccessControlType)
            Console.WriteLine("      Rights: {0}", ar.SemaphoreRights)
            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

Comentarios

La regla solo se quita si coincide rule exactamente con todos los detalles, incluidas las marcas. Otras reglas con el mismo usuario y AccessControlType no se ven afectadas.

Importante

Una regla representa una o varias entradas de control de acceso subyacentes (ACE), y estas entradas se dividen o combinan según sea necesario al modificar las reglas de seguridad de acceso para un usuario. Por lo tanto, es posible que una regla ya no exista en la forma específica que tenía cuando se agregó y, en ese caso, el RemoveAccessRuleSpecific método no puede quitarla.

Se aplica a