DnsPermissionAttribute.DnsPermissionAttribute Constructor

Initializes a new instance of the DnsPermissionAttribute class with the specified SecurityAction value.

Namespace: System.Net
Assembly: System (in system.dll)

Public Sub New ( _
	action As SecurityAction _
Dim action As SecurityAction

Dim instance As New DnsPermissionAttribute(action)
public DnsPermissionAttribute (
	SecurityAction action
public function DnsPermissionAttribute (
	action : SecurityAction
Not applicable.



One of the SecurityAction values.

Exception typeCondition


The action parameter is not a valid SecurityAction.

The SecurityAction value that is passed to this constructor specifies the allowable DnsPermissionAttribute targets.

The following example uses DnsPermissionAttribute to apply declarative security to a custom class.

' Uses the DnsPermissionAttribute to restrict access only to those who have permission.
<DnsPermission(SecurityAction.Demand, Unrestricted := true)>  _
Public Class MyClass1
   Public Shared Function GetIPAddress() As IPAddress
      Dim ipAddress As IPAddress = Dns.Resolve("localhost").AddressList(0)
      Return ipAddress
   End Function 'GetIPAddress
   Public Shared Sub Main()
         ' Grants Access.
         Console.WriteLine(("Access granted" + ControlChars.NewLine + " The local host IP Address is :" + MyClass1.GetIPAddress().ToString()))
      ' Denies Access.
      Catch securityException As SecurityException
         Console.WriteLine("Access denied")
      End Try
   End Sub 'Main 
End Class '[MyClass1]

// Uses the DnsPermissionAttribute to restrict access only to those who 
// have permission.
/** @attribute DnsPermission(SecurityAction.Demand, Unrestricted = true)
public class MyClass
    public static IPAddress GetIPAddress()
        IPAddress ipAddress = (IPAddress)Dns.Resolve(

        return ipAddress;
    } //GetIPAddress

    public static void main(String[] args)
        try {
            //Grants Access.
            Console.WriteLine(" Access granted\n The local host IP " 
                + "Address is :" + MyClass.GetIPAddress().ToString());
        // Denies Access.
        catch (System.Security.SecurityException securityException) {
            Console.WriteLine("Access denied");
    } //main
} //MyClass

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0