public void UseDns() {
   // Create a DnsPermission instance.
   DnsPermission myPermission = new DnsPermission(PermissionState.Unrestricted);
   // Check for permission.
   myPermission.Demand();
   // Create an identical copy of the above 'DnsPermission' object.
   DnsPermission myPermissionCopy = (DnsPermission)myPermission.Copy();
   Console.WriteLine("Attributes and Values of 'DnsPermission' instance :");
   // Print the attributes and values.
   PrintKeysAndValues(myPermission.ToXml().Attributes);
   Console.WriteLine("Attribute and values of copied instance :");
   PrintKeysAndValues(myPermissionCopy.ToXml().Attributes);
}

private void PrintKeysAndValues(Hashtable myHashtable) {
   // Get the enumerator that can iterate through the hash table.
   IDictionaryEnumerator myEnumerator = myHashtable.GetEnumerator();
   Console.WriteLine("\t-KEY-\t-VALUE-");
   while (myEnumerator.MoveNext())
      Console.WriteLine("\t{0}:\t{1}", myEnumerator.Key, myEnumerator.Value);
   Console.WriteLine();
}