SemaphoreSecurity.AddAccessRule(SemaphoreAccessRule) Method

public:
 void AddAccessRule(System::Security::AccessControl::SemaphoreAccessRule ^ rule);

public void AddAccessRule (System.Security.AccessControl.SemaphoreAccessRule rule);

override this.AddAccessRule : System.Security.AccessControl.SemaphoreAccessRule -> unit

Public Sub AddAccessRule (rule As SemaphoreAccessRule)

Parameters

Exceptions

Examples

The following code example demonstrates the separation between Allow rules and Deny rules, and shows the combination of rights in compatible rules. The example creates a SemaphoreSecurity object, adds rules that allow and deny various rights for the current user, and displays the resulting pair of rules. The example then allows new rights for the current user and displays the result, showing that the new rights are merged with the existing Allow rule.

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.
        SemaphoreAccessRule rule = new SemaphoreAccessRule(user, 
            SemaphoreRights.Synchronize | SemaphoreRights.Modify, 
            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);

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


Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

        User: TestDomain\TestUser
        Type: Allow
      Rights: Modify, ReadPermissions, 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.
        Dim rule As New SemaphoreAccessRule(user, _
            SemaphoreRights.Synchronize _
            Or SemaphoreRights.Modify, _
            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)

        ' Add a rule that allows the current user the 
        ' right to read permissions on the semaphore. This 
        ' rule is merged with the existing Allow rule.
        rule = New SemaphoreAccessRule(user, _
            SemaphoreRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(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, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, ReadPermissions, Synchronize

Remarks

The AddAccessRule method searches for rules with the same user or group and the same AccessControlType as rule. If none are found, rule is added. If a matching rule is found, the rights in rule are merged with the existing rule.

Applies to