DnsPermission.Union(IPermission) 方法

定义

创建一个是当前权限实例与指定权限实例的并集的权限实例。

public:
 override System::Security::IPermission ^ Union(System::Security::IPermission ^ target);
public override System.Security.IPermission Union (System.Security.IPermission target);
override this.Union : System.Security.IPermission -> System.Security.IPermission
Public Overrides Function Union (target As IPermission) As IPermission

参数

target
IPermission

要与当前实例组合的 DnsPermission 实例。

返回

一个 DnsPermission 实例,表示当前 DnsPermission 实例与指定 DnsPermission 实例的并集。 如果 targetnull,则该方法将返回当前实例的一个副本。 如果当前实例或 target 是不受限制的,则此方法返回不受限制的 DnsPermission 实例;否则,返回受限制的 DnsPermission 实例。

例外

target 既不是 DnsPermission,也不是 null

示例

以下示例创建一个权限实例,该实例是当前权限实例和指定权限实例的并集。

private:
   void MyUnion()
   {
      // Create a DnsPermission instance that is the union of the current DnsPermission
      // instance and the specified DnsPermission instance.
      DnsPermission^ permission = dynamic_cast<DnsPermission^>(dnsPermission1->Union( dnsPermission2 ));
      // Print the attributes and the values of the union instance of DnsPermission.
      PrintKeysAndValues( permission->ToXml()->Attributes );
   }

public:
   void useDns()
   {
      // Create a DnsPermission instance.
      dnsPermission1 = gcnew DnsPermission( PermissionState::Unrestricted );
      dnsPermission2 = gcnew DnsPermission( PermissionState::None );
      // Check for permission.
      dnsPermission1->Demand();
      dnsPermission2->Demand();
      Console::WriteLine( "Attributes and Values of first DnsPermission instance :" );
      PrintKeysAndValues( dnsPermission1->ToXml()->Attributes );
      Console::WriteLine( "Attributes and Values of second DnsPermission instance :" );
      PrintKeysAndValues( dnsPermission2->ToXml()->Attributes );
      Console::WriteLine( "Union of both instances : " );
      MyUnion();
      Console::WriteLine( "Intersection of both instances : " );
      MyIntersection();
   }

private:
   void PrintKeysAndValues( Hashtable^ myList )
   {
      // Get the enumerator that can iterate through the hash tabble.
      IDictionaryEnumerator^ myEnumerator = myList->GetEnumerator();
      Console::WriteLine( "\t-KEY-\t-VALUE-" );
      while ( myEnumerator->MoveNext() )
      {
         Console::WriteLine( "\t {0}:\t {1}", myEnumerator->Key, myEnumerator->Value );
      }
      Console::WriteLine();
   }
private void MyUnion()
{
   // Create a DnsPermission instance that is the union of the current DnsPermission
   // instance and the specified DnsPermission instance.
   DnsPermission permission = (DnsPermission)dnsPermission1.Union(dnsPermission2);
   // Print the attributes and the values of the union instance of DnsPermission.
   PrintKeysAndValues(permission.ToXml().Attributes);
}
public void useDns() {
   // Create a DnsPermission instance.
   dnsPermission1 = new DnsPermission(PermissionState.Unrestricted);
   dnsPermission2 = new DnsPermission(PermissionState.None);
   // Check for permission.
   dnsPermission1.Demand();
   dnsPermission2.Demand();
   Console.WriteLine("Attributes and Values of first DnsPermission instance :");
   PrintKeysAndValues(dnsPermission1.ToXml().Attributes);
   Console.WriteLine("Attributes and Values of second DnsPermission instance :");
   PrintKeysAndValues(dnsPermission2.ToXml().Attributes);
   Console.WriteLine("Union of both instances : ");
   MyUnion();
   Console.WriteLine("Intersection of both instances : ");
   MyIntersection();
}

private void PrintKeysAndValues(Hashtable myList) {
   // Get the enumerator that can iterate through the hash tabble.
   IDictionaryEnumerator myEnumerator = myList.GetEnumerator();
   Console.WriteLine("\t-KEY-\t-VALUE-");
   while (myEnumerator.MoveNext())
      Console.WriteLine("\t{0}:\t{1}", myEnumerator.Key, myEnumerator.Value);
   Console.WriteLine();
}
Private Sub MyUnion()
    ' Create a DnsPermission instance which is the union of the current DnsPermission instance and the specified DnsPermission instance.
    Dim permission As DnsPermission = CType(dnsPermission1.Union(dnsPermission2), DnsPermission)
    ' Print the attributes and values of the union instance of DnsPermission.
    PrintKeysAndValues(permission.ToXml().Attributes)
End Sub
Public Sub useDns()
    ' Create a DnsPermission instance.
    dnsPermission1 = New DnsPermission(PermissionState.Unrestricted)
    dnsPermission2 = New DnsPermission(PermissionState.None)
    ' Check for permission.
    dnsPermission1.Demand()
    dnsPermission2.Demand()
    Console.WriteLine("Attributes and Values of first DnsPermission instance :")
    PrintKeysAndValues(dnsPermission1.ToXml().Attributes)
    Console.WriteLine("Attributes and Values of second DnsPermission instance :")
    PrintKeysAndValues(dnsPermission2.ToXml().Attributes)
    Console.WriteLine("Union of both instances : ")
    MyUnion()
    Console.WriteLine("Intersection of both instances : ")
    MyIntersection()
End Sub

Private Sub PrintKeysAndValues(myList As Hashtable)
    ' Get the enumerator that can iterate through the hash table.
    Dim myEnumerator As IDictionaryEnumerator = myList.GetEnumerator()
    Console.WriteLine(ControlChars.Tab + "-KEY-" + ControlChars.Tab + "-VALUE-")
    While myEnumerator.MoveNext()
        Console.WriteLine(ControlChars.Tab + "{0}:" + ControlChars.Tab + "{1}", myEnumerator.Key, myEnumerator.Value)
    End While
    Console.WriteLine()
End Sub

注解

方法 Union 返回一个 DnsPermission 实例,该实例允许当前 DnsPermission 实例或指定 DnsPermission 实例定义的访问。 通过任一权限的任何要求都会通过其联合。

适用于