Fix GetDefaultLocalAddress (#65)

Author: josesimoes

source/nanoFramework.System.Net/IPAddress.cs

@@ -4,6 +4,8 @@
 // See LICENSE file in the project root for full license information.
 //
 
+using System.Net.NetworkInformation;
+
 namespace System.Net
 {
     /// <summary>
@@ -195,52 +197,26 @@ private static int ConvertStringToInt32(string value)
         /// <returns>The default IP address.</returns>
         public static IPAddress GetDefaultLocalAddress()
         {
-            // Special conditions are implemented here because of a problem with GetHostEntry
-            // on the digi device and NetworkInterface from the emulator.
-            // In the emulator we must use GetHostEntry.
-            // On the device and Windows NetworkInterface works and is preferred.
-            try
-            {
-                //NetworkInterface[] interfaces = NetworkInterface.GetAllNetworkInterfaces();
-
-                //int cnt = interfaces.Length;
-                //for (int i = 0; i < cnt; i++)
-                //{
-                //    NetworkInterface ni = interfaces[i];
+            NetworkInterface[] interfaces = NetworkInterface.GetAllNetworkInterfaces();
 
-                //    if (ni.IPAddress != "0.0.0.0" && ni.SubnetMask != "0.0.0.0")
-                //    {
-                //        return IPAddress.Parse(ni.IPAddress);
-                //    }
-                //}
-            }
-            catch
+            int cnt = interfaces.Length;
+            for (int i = 0; i < cnt; i++)
             {
-            }
+                NetworkInterface ni = interfaces[i];
 
-            try
-            {
-                IPAddress localAddress = null;
-              //  IPHostEntry hostEntry = Dns.GetHostEntry("");
-                IPHostEntry hostEntry = new IPHostEntry();
-
-                int cnt = hostEntry.AddressList.Length;
-                for (int i = 0; i < cnt; ++i)
+                if (ni.IPv4Address != "0.0.0.0" && ni.IPv4SubnetMask != "0.0.0.0")
                 {
-                    if ((localAddress = hostEntry.AddressList[i]) != null)
-                    {
-                        if(localAddress.m_Address != 0)
-                        {
-                            return localAddress;
-                        }
-                    }
+                    return Parse(ni.IPv4Address);
                 }
-            }
-            catch
-            {
+                // FIXME
+                // TODO implement this when IPv6 support is added
+                //else (ni.IPv6Address != "0.0.0.0" )
+                //{
+                //    return IPAddress.Parse(ni.IPv6Address);
+                //}
             }
 
-            return IPAddress.Any;
+            return Any;
         }   
     }
 }