SemaphoreSecurity.RemoveAccessRule(SemaphoreAccessRule) Metodo

public:
 bool RemoveAccessRule(System::Security::AccessControl::SemaphoreAccessRule ^ rule);

public bool RemoveAccessRule (System.Security.AccessControl.SemaphoreAccessRule rule);

override this.RemoveAccessRule : System.Security.AccessControl.SemaphoreAccessRule -> bool

Public Function RemoveAccessRule (rule As SemaphoreAccessRule) As Boolean

Parametri

Restituisce

true se viene trovata una regola compatibile; in caso contrario, false.

Eccezioni

Esempio

Nell'esempio di codice seguente viene illustrato l'uso del RemoveAccessRule metodo per rimuovere i diritti da una Allow regola in un SemaphoreSecurity oggetto . Mostra inoltre che altri diritti in rule vengono ignorati.

Nell'esempio viene creato un SemaphoreSecurity oggetto e vengono aggiunte regole che consentono e negano vari diritti per l'utente corrente. I diritti consentiti includono Modify, ReadPermissionse Synchronize. Nell'esempio viene quindi creata una nuova regola per l'utente corrente, inclusi ReadPermissions i diritti e TakeOwnership e viene usata con il RemoveAccessRule metodo per rimuovere ReadPermissions dalla Allow regola nell'oggetto SemaphoreSecurity . Il diritto estraneo TakeOwnership in rule viene ignorato.

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 and read the
        // permissions on the semaphore.
        SemaphoreAccessRule rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.Synchronize | SemaphoreRights.Modify
                | SemaphoreRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        // Add a rule that denies the current user the 
        // right to change permissions on the semaphore.
        rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.ChangePermissions, 
            AccessControlType.Deny);
        mSec.AddAccessRule(rule);

        // Display the rules in the security object.
        ShowSecurity(mSec);

        // Create a rule that grants the current user 
        // the right to read permissions on the semaphore, and
        // take ownership of the semaphore. Use this rule to 
        // remove the right to read permissions from the 
        // Allow rule for the current user. The inclusion 
        // of the right to take ownership has no effect.
        rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.TakeOwnership | 
                SemaphoreRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.RemoveAccessRule(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, ReadPermissions, Synchronize


Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

        User: TestDomain\TestUser
        Type: Allow
      Rights: Modify, Synchronize
 */

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, and to 
        ' read its permissions.
        Dim rule As New SemaphoreAccessRule(user, _
            SemaphoreRights.Synchronize _
            Or SemaphoreRights.Modify _
            Or SemaphoreRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ' Add a rule that denies the current user the 
        ' right to change permissions on the semaphore.
        rule = New SemaphoreAccessRule(user, _
            SemaphoreRights.ChangePermissions, _
            AccessControlType.Deny)
        mSec.AddAccessRule(rule)

        ' Display the rules in the security object.
        ShowSecurity(mSec)

        ' Create a rule that grants the current user 
        ' the right to read permissions on the semaphore, and
        ' take ownership of the semaphore. Use this rule to 
        ' remove the right to read permissions from the 
        ' Allow rule for the current user. The inclusion 
        ' of the right to take ownership has no effect.
        rule = New SemaphoreAccessRule(user, _
            SemaphoreRights.TakeOwnership _
            Or SemaphoreRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.RemoveAccessRule(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, ReadPermissions, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, Synchronize

Commenti

Viene eseguita la ricerca di SemaphoreSecurity una regola con lo stesso utente e lo stesso AccessControlType valore di rule. Se non viene trovata alcuna regola di questo tipo, non viene eseguita alcuna azione e il metodo restituisce false. Se vengono trovate regole di corrispondenza, l'ereditarietà e i flag di compatibilità vengono verificati per verificare la compatibilità con i flag specificati in rule. Se non viene trovata alcuna regola compatibile, non viene eseguita alcuna azione e il metodo restituisce false. Se viene trovata una regola con flag compatibili, i diritti specificati in rule vengono rimossi dalla regola compatibile e il metodo restituisce true. Se rule specifica diritti non contenuti nella regola compatibile, non viene eseguita alcuna azione rispetto a tali diritti. Se tutti i diritti vengono rimossi dalla regola compatibile, l'intera regola viene rimossa dall'oggetto corrente SemaphoreSecurity .

Si applica a