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EventWaitHandleSecurity.RemoveAccessRuleAll(EventWaitHandleAccessRule) Method

Definition

Searches for all access control rules with the same user and AccessControlType (allow or deny) as the specified rule and, if found, removes them.

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

Parameters

rule
EventWaitHandleAccessRule

An EventWaitHandleAccessRule that specifies the user and AccessControlType to search for. Any rights specified by this rule are ignored.

Exceptions

rule is null.

Examples

The following code example shows that the RemoveAccessRuleAll method removes all rules that match user and AccessControlType, ignoring rights.

The example creates an EventWaitHandleSecurity object, adds rules that allow and deny various rights for the current user, and then merges additional rights into the Allow rule. The example then creates a new rule that allows the current user to take ownership, and uses that rule to remove the Allow rule from the EventWaitHandleSecurity object.

Note

This example does not attach the security object to a EventWaitHandle object. Examples that attach security objects can be found in EventWaitHandle.GetAccessControl and EventWaitHandle.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.
        EventWaitHandleSecurity mSec = new EventWaitHandleSecurity();

        // Add a rule that grants the current user the 
        // right to wait on or signal the event.
        EventWaitHandleAccessRule rule = new EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify, 
            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);

        // Add a rule that allows the current user the 
        // right to read permissions on the event. This rule
        // is merged with the existing Allow rule.
        rule = new EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        ShowSecurity(mSec);

        // Create a rule that allows the current user to
        // take ownership of the event, and use that rule 
        // to remove the existing Allow rule from the
        // EventWaitHandleSecurity object, showing that the user
        // and access type must match, while the rights are
        // ignored.
        Console.WriteLine("Use RemoveAccessRuleAll to remove the Allow rule.");
        rule = new EventWaitHandleAccessRule(user, 
            EventWaitHandleRights.TakeOwnership, 
            AccessControlType.Allow);
        mSec.RemoveAccessRuleAll(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, Synchronize


Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

        User: TestDomain\TestUser
        Type: Allow
      Rights: Modify, ReadPermissions, Synchronize

Use RemoveAccessRuleAll to remove the Allow rule.

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 EventWaitHandleSecurity()

        ' Add a rule that grants the current user the 
        ' right to wait on or signal the event.
        Dim rule As New EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.Synchronize _
            Or EventWaitHandleRights.Modify, _
            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)

        ' Add a rule that allows the current user the 
        ' right to read permissions on the event. This rule
        ' is merged with the existing Allow rule.
        rule = New EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ShowSecurity(mSec)

        ' Create a rule that allows the current user to
        ' take ownership of the event, and use that rule 
        ' to remove the existing allow access rule from 
        ' the EventWaitHandleSecurity object, showing that the user
        ' and access type must match, while the rights are
        ' ignored.
        Console.WriteLine("Use RemoveAccessRuleAll to remove the Allow rule.")
        rule = New EventWaitHandleAccessRule(user, _
            EventWaitHandleRights.TakeOwnership, _
            AccessControlType.Allow)
        mSec.RemoveAccessRuleAll(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, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, ReadPermissions, Synchronize
'
'Use RemoveAccessRuleAll to remove the Allow rule.
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions

Remarks

The current EventWaitHandleSecurity is searched for rules that have the same user and the same AccessControlType value as rule. Any rights specified by rule are ignored when performing this search. All matching rules are removed. If no matching rules are found, no action is taken.

Applies to