MutexSecurity.RemoveAccessRuleSpecific(MutexAccessRule) Metode

Definisi

Ruang nama:

System.Security.AccessControl

Rakitan:

System.Threading.AccessControl.dll

Mencari aturan kontrol akses yang sama persis dengan aturan yang ditentukan dan, jika ditemukan, akan menghapusnya.

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

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

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

Public Sub RemoveAccessRuleSpecific (rule As MutexAccessRule)

Parameter

rule

MutexAccessRule

yang MutexAccessRule akan dihapus.

Pengecualian

ArgumentNullException

ruleadalah null.

Contoh

Contoh kode berikut menunjukkan bahwa metode memerlukan kecocokan RemoveAccessRuleSpecific yang tepat untuk menghapus aturan, dan bahwa aturan untuk mengizinkan dan menolak hak independen satu sama lain.

Contoh membuat MutexSecurity objek, menambahkan aturan yang mengizinkan dan menolak berbagai hak untuk pengguna saat ini, lalu menggabungkan hak tambahan ke Allow dalam aturan akses. Contoh kemudian meneruskan aturan asli Allow ke RemoveAccessRuleSpecific metode , dan menampilkan hasilnya, menunjukkan bahwa tidak ada yang dihapus. Contoh kemudian membuat aturan yang cocok dengan Allow aturan dalam MutexSecurity objek, dan berhasil menggunakan RemoveAccessRuleSpecific metode untuk menghapus aturan.

Catatan

Contoh ini tidak melampirkan objek keamanan ke Mutex objek. Contoh yang melampirkan objek keamanan dapat ditemukan di Mutex.GetAccessControl dan 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.
        MutexAccessRule ruleA = new MutexAccessRule(user, 
            MutexRights.Synchronize | MutexRights.Modify, 
            AccessControlType.Allow);
        mSec.AddAccessRule(ruleA);

        // Add a rule that denies the current user the 
        // right to change permissions on the mutex.
        MutexAccessRule rule = new MutexAccessRule(user, 
            MutexRights.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 mutex. This rule
        // is merged with the existing Allow rule.
        rule = new MutexAccessRule(user, 
            MutexRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.AddAccessRule(rule);

        ShowSecurity(mSec);

        // Attempt to remove the original rule (granting
        // the right to enter or release the mutex) with 
        // RemoveAccessRuleSpecific. The removal fails,
        // because the right to read the permissions on the 
        // mutex has been added to the rule, so that it no 
        // longer matches the original rule.
        Console.WriteLine("Attempt to use RemoveAccessRuleSpecific on the original rule.");
        mSec.RemoveAccessRuleSpecific(ruleA);

        ShowSecurity(mSec);

        // Create a rule that grants the current user 
        // the right to enter or release the mutex, and
        // to read permissions. Use this rule to remove
        // the Allow rule for the current user.
        Console.WriteLine("Use RemoveAccessRuleSpecific with the correct rights.");
        rule = new MutexAccessRule(user, 
            MutexRights.Synchronize | MutexRights.Modify | 
                MutexRights.ReadPermissions, 
            AccessControlType.Allow);
        mSec.RemoveAccessRuleSpecific(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, Synchronize


Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

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

Attempt to use RemoveAccessRuleSpecific on the original rule.

Current access rules:

        User: TestDomain\TestUser
        Type: Deny
      Rights: ChangePermissions

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

Use RemoveAccessRuleSpecific with the correct rights.

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 MutexSecurity()

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

        ' Add a rule that denies the current user the 
        ' right to change permissions on the mutex.
        Dim rule As New MutexAccessRule(user, _
            MutexRights.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 mutex. This rule
        ' is merged with the existing Allow rule.
        rule = New MutexAccessRule(user, _
            MutexRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.AddAccessRule(rule)

        ShowSecurity(mSec)

        ' Attempt to remove the original rule (granting
        ' the right to enter or release the mutex) with 
        ' RemoveAccessRuleSpecific. The removal fails,
        ' because the right to read the permissions on the 
        ' mutex has been added to the rule, so that it no 
        ' longer matches the original rule.
        Console.WriteLine("Attempt to use RemoveAccessRuleSpecific on the original rule.")
        mSec.RemoveAccessRuleSpecific(ruleA)

        ShowSecurity(mSec)

        ' Create a rule that grants the current user 
        ' the right to enter or release the mutex, and
        ' to read permissions. Use this rule to remove
        ' the Allow rule for the current user.
        Console.WriteLine("Use RemoveAccessRuleSpecific with the correct rights.")
        rule = New MutexAccessRule(user, _
            MutexRights.Synchronize _
            Or MutexRights.Modify _
            Or MutexRights.ReadPermissions, _
            AccessControlType.Allow)
        mSec.RemoveAccessRuleSpecific(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, Synchronize
'
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, ReadPermissions, Synchronize
'
'Attempt to use RemoveAccessRuleSpecific on the original rule.
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions
'
'        User: TestDomain\TestUser
'        Type: Allow
'      Rights: Modify, ReadPermissions, Synchronize
'
'Use RemoveAccessRuleSpecific with the correct rights.
'
'Current access rules:
'
'        User: TestDomain\TestUser
'        Type: Deny
'      Rights: ChangePermissions

Keterangan

Aturan dihapus hanya jika persis cocok rule di semua detail, termasuk bendera. Aturan lain dengan pengguna yang sama dan AccessControlType tidak terpengaruh.

Penting

Aturan mewakili satu atau beberapa entri kontrol akses (ACE) yang mendasarinya, dan entri ini dipisahkan atau digabungkan seperlunya saat Anda mengubah aturan keamanan akses untuk pengguna. Dengan demikian, aturan mungkin tidak lagi ada dalam bentuk tertentu yang dimilikinya ketika ditambahkan, dan dalam hal RemoveAccessRuleSpecific ini metode tidak dapat menghapusnya.