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Networking In The Hand includes a full desktop-compatible implementation of the FtpWebRequest class. This plugs into the WebRequest class so that calling WebRequest.Create() with an FTP Uri will create an object of type FtpWebRequest. Because FTP support isn’t built into the Compact Framework you have to register the class with this prefix using the the following code (only required once in your code):-

InTheHand.Net.FtpWebRequest.RegisterPrefix();

We have already looked at performing simple operations with the WebClient class. for more complex FTP operations you can use the FtpWebRequest directly. For example retrieving the modification date of a specific file:-

FtpWebRequest requestDate = (FtpWebRequest)FtpWebRequest.Create(requestUri);
requestDate.Method = WebRequestMethods.Ftp.GetDateTimestamp;
if (wc.Credentials != null)
{
   requestDate.Credentials = wc.Credentials;
}
FtpWebResponse responseDate = null;

responseDate = (FtpWebResponse)requestDate.GetResponse();

if (responseDate != null)
{
   MessageBox.Show(responseDate.LastModified.ToString());
   responseDate.Close();
}

Networking In The Hand includes the WebClient class which is a helper class which makes it easier to do uploading and downloading of data using HTTP and FTP transports. For example rather than creating an HttpWebRequest, setting a number of properties, getting the response and reading the response stream and copying the data into a file, why not use DownloadFile to perform a single operation to write the data from a specific Uri to a local file:-

WebClient wc = new WebClient();
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
   wc.DownloadFile(uriTarget, saveFileDialog1.FileName);
}

Additional methods provide the ability to download a string, and download a byte array containing the data. There are a similar set of operations for uploading:-

if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
   wc.UploadFile(uriDestination, openFileDialog1.FileName);
}

Not only does this work with the HTTP transport, but also with the FTP support which is also part of the library – the only difference is the Uri that you pass in. If your site requires a username/password you can set the Credentials property of the WebClient once and they will be used for all subsequent operations.

Networking In The Hand includes the Ping class (In the InTheHand.Net.NetworkInformation namespace). The component allows you to determine if a network path to a particular host is available and whether the host is responding. It doesn’t guarantee that a particular service is running on the server (HTTP, FTP etc). You can perform a Ping in a couple of lines of code, the class has been designed to be an exact subset of the equivalent class in the full .NET framework. The following is an example of the simplest ping request using a default payload and timeout settings.

InTheHand.Net.NetworkInformation.Ping p = new InTheHand.Net.NetworkInformation.Ping();
InTheHand.Net.NetworkInformation.PingReply reply = p.Send(“www.google.com”);

if (reply.Status == IPStatus.Success)
{
   string message = string.Format(“Address: {0}rnRoundTrip time: {1}rnTime to live: {2}rnDon’t fragment: {3}rnBuffer size: {0}”,
      reply.Address.ToString(),
      reply.RoundtripTime,
      reply.Options.Ttl,
      reply.Options.DontFragment,
      reply.Buffer.Length);

   MessageBox.Show(message, “Ping”);
}
else
{
   MessageBox.Show(reply.Status.ToString(), “Ping”);
}

The class allows you to further customise the request. You can specify your own data payload for example, or set a different timeout value (the default is 5 seconds).

Networking In The Hand 2.0 offers a new dialog which allows you to prompt the user for networking credentials. The dialog is designed for the best appearance depending on your platform, for example the screenshots below show both Windows Mobile 5.0 Pocket PC and Windows Mobile 6 Standard Landscape:-

If your application stores authentication details you can pre-populate the dialog. Optionally you can display a Save Settings checkbox on the form. The following code snippet shows how to display the dialog and return the credentials as an ICredentials object:-

private ICredentials GetCredentials(string resourceName)
{
   InTheHand.Windows.Forms.AuthenticationDialog ad = new InTheHand.Windows.Forms.AuthenticationDialog();

   ad.ResourceName = resourceName;
   if(ad.ShowDialog() == DialogResult.OK)
   {
        return new NetworkCredential(ad.Username, ad.Password, ad.Domain);
   }
   else
   {
      return null;
   }

}