EventWaitHandleSecurity.RemoveAccessRule(EventWaitHandleAccessRule) 方法

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

參數

傳回

true若找到相容規則;否則，。 false

例外狀況

範例

以下程式碼範例示範了如何使用此RemoveAccessRule方法移除物件中Allow規則的權限EventWaitHandleSecurity。 這也顯示其他權利 rule 被忽視了。

範例中建立一個 EventWaitHandleSecurity 物件，並加入允許或拒絕當前使用者各種權利的規則。 允許的權利包括 Modify、 ReadPermissions、 Synchronize和 。 範例接著為目前使用者建立一條新規則，包含 ReadPermissions 和 TakeOwnership 權限，並利用該規則RemoveAccessRule與物件中ReadPermissions移除AllowEventWaitHandleSecurity該規則的方法。 TakeOwnership右入rule則被忽略。

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

備註

EventWaitHandleSecurity目前會搜尋具有相同使用者且值AccessControlType相同的rule規則。 若未找到此類規則，則不執行任何操作，方法返回 false。 若找到匹配規則，則檢查其繼承與相容性標誌是否與 中 rule指定的標誌相容。 若未找到相容規則，則不執行任何動作，方法返回 false。 若找到具有相容標誌的規則，則將 中 rule 指定的權利從相容規則中移除，並返回 true。 若 rule 指定相容規則中未包含的權利，則不對該權利採取任何行動。 若相容規則中移除所有權利，則整個規則將從當前 EventWaitHandleSecurity 物件中移除。