MutexSecurity.ResetAccessRule(MutexAccessRule) Metodo

Definizione

Spazio dei nomi:

System.Security.AccessControl

Assembly:

System.Threading.AccessControl.dll

Assembly:

mscorlib.dll

Rimuove tutte le regole di controllo di accesso con lo stesso utente della regola specificata, a prescindere dalla classe AccessControlType, quindi aggiunge la regola specificata.

public:
 void ResetAccessRule(System::Security::AccessControl::MutexAccessRule ^ rule);

public void ResetAccessRule (System.Security.AccessControl.MutexAccessRule rule);

override this.ResetAccessRule : System.Security.AccessControl.MutexAccessRule -> unit

Public Sub ResetAccessRule (rule As MutexAccessRule)

Parametri

rule

MutexAccessRule

Oggetto MutexAccessRule da aggiungere. L'utente specificato dalla regola determina le regole da rimuovere prima di aggiungere questa regola.

Eccezioni

ArgumentNullException

rule è null.

Esempio

Nell'esempio di codice seguente viene illustrato come il ResetAccessRule metodo sostituisce tutte le regole per l'utente corrispondente con la regola specificata per la corrispondenza.

L'esempio crea un MutexSecurity oggetto e aggiunge regole che consentono e negano vari diritti per l'utente corrente. L'esempio crea quindi una nuova regola che consente al controllo completo dell'utente corrente e usa il ResetAccessRule metodo per sostituire entrambe le regole esistenti con la nuova regola.

Nota

In questo esempio non viene collegato l'oggetto di sicurezza a un Mutex oggetto. Gli esempi che allegano oggetti di sicurezza sono disponibili in Mutex.GetAccessControl e Mutex.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.
        MutexSecurity mSec = new MutexSecurity();

        // Add a rule that grants the current user the 
        // right to enter or release the mutex and read the
        // permissions on the mutex.
        MutexAccessRule rule = new MutexAccessRule(user, 
            MutexRights.Synchronize | MutexRights.Modify
                | MutexRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

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

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

        // Create a rule that grants the current user 
        // the full control over the mutex. Use the
        // ResetAccessRule method to replace both of 
        // the existing rules with the new rule. 
        rule = new MutexAccessRule(user,
            MutexRights.FullControl,
            AccessControlType.Allow);
        mSec.ResetAccessRule(rule);

        ShowSecurity(mSec);
    }

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

        foreach(MutexAccessRule 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.MutexRights);
            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: Allow
      Rights: FullControl
 */

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 MutexSecurity()

        ' Add a rule that grants the current user the 
        ' right to enter or release the mutex, and to 
        ' read its permissions.
        Dim rule As New MutexAccessRule(user, _
            MutexRights.Synchronize _
            Or MutexRights.Modify _
            Or MutexRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

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

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

        ' Create a rule that grants the current user 
        ' the full control over the mutex. Use the
        ' ResetAccessRule method to replace both of 
        ' the existing rules with the new rule. 
        rule = New MutexAccessRule(user, _
            MutexRights.FullControl, _
            AccessControlType.Allow)
        mSec.ResetAccessRule(rule)

        ShowSecurity(mSec)
        
    End Sub 

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

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

            Console.WriteLine("        User: {0}", ar.IdentityReference)
            Console.WriteLine("        Type: {0}", ar.AccessControlType)
            Console.WriteLine("      Rights: {0}", ar.MutexRights)
            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: Allow
'      Rights: FullControl

Commenti

Se non sono presenti regole di accesso con cui l'utente corrisponde alla regola specificata, rule viene aggiunto.