EventWaitHandleSecurity.RemoveAccessRule(EventWaitHandleAccessRule) Metod

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

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

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

Public Function RemoveAccessRule (rule As EventWaitHandleAccessRule) As Boolean

Parametrar

Returer

trueom en kompatibel regel hittas; annars . false

Undantag

Exempel

I följande kodexempel visas hur metoden används RemoveAccessRule för att ta bort rättigheter från en Allow regel i ett EventWaitHandleSecurity objekt. Det visar också att andra rättigheter i rule ignoreras.

Exemplet skapar ett EventWaitHandleSecurity objekt och lägger till regler som tillåter och nekar olika rättigheter för den aktuella användaren. De rättigheter som tillåts är Modify, ReadPermissionsoch Synchronize. Exemplet skapar sedan en ny regel för den aktuella användaren, inklusive ReadPermissions och TakeOwnership rättigheter, och använder den RemoveAccessRule regeln med metoden för att ta bort ReadPermissions från Allow regeln i EventWaitHandleSecurity objektet. Rätten TakeOwnership i rule ignoreras.

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 and read the
        // permissions on the event.
        EventWaitHandleAccessRule rule = new EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify
                | EventWaitHandleRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        // Add a rule that denies the current user the 
        // right to change permissions on the event.
        rule = new EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.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 event, and
        // take ownership of the event. 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 EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.TakeOwnership | 
                EventWaitHandleRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.RemoveAccessRule(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, 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 EventWaitHandleSecurity()

        ' Add a rule that grants the current user the 
        ' right to wait on or signal the event, and to 
        ' read its permissions.
        Dim rule As New EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.Synchronize _
            Or EventWaitHandleRights.Modify _
            Or EventWaitHandleRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ' Add a rule that denies the current user the 
        ' right to change permissions on the event.
        rule = New EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.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 event, and
        ' take ownership of the event. 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 EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.TakeOwnership _
            Or EventWaitHandleRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.RemoveAccessRule(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, ReadPermissions, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, Synchronize

Kommentarer

Den aktuella EventWaitHandleSecurity söks efter en regel som har samma användare och samma AccessControlType värde som rule. Om ingen sådan regel hittas vidtas ingen åtgärd och metoden returnerar false. Om matchande regler hittas kontrolleras deras arvs- och kompatibilitetsflaggor för kompatibilitet med flaggorna som anges i rule. Om ingen kompatibel regel hittas vidtas ingen åtgärd och metoden returnerar false. Om en regel med kompatibla flaggor hittas tas de rättigheter som anges i rule bort från den kompatibla regeln och metoden returnerar true. Om rule anger rättigheter som inte ingår i den kompatibla regeln vidtas inga åtgärder med avseende på dessa rättigheter. Om alla rättigheter tas bort från den kompatibla regeln tas hela regeln bort från det aktuella EventWaitHandleSecurity objektet.