C# 5.0 includes the async and await keywords to ease writing of asynchronous code

In Windows Store Apps, new Task-based methods are used for networking exclusively ,not supported on Windows Phone 8

Solutions for Windows Phone are available:

API WP7.1 WP8 W8

System.Net.WebClient

System.Net.HttpWebRequest (async only)

System.Net.Http.HttpClient (NuGet) (NuGet)

Windows.Web.Syndication.SyndicationClient

Windows.Web.AtomPub.AtomPubClient

ASMX Web Services

WCF Services

OData Services

using System.Net;...

WebClient client;

public MainPage(){

...client = new WebClient();client.DownloadStringCompleted += client_DownloadStringCompleted;

}

void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e){

this.downloadedText = e.Result;}

private void loadButton_Click(object sender, RoutedEventArgs e){

client.DownloadStringAsync(new Uri("http://MyServer/ServicesApplication/rssdump.xml"));}

using System.Net;using System.Threading.Tasks;...

private async void LoadWithWebClient(){

var client = new WebClient();string response = await client.DownloadStringTaskAsync(

new Uri("http://MyServer/ServicesApplication/rssdump.xml"));this.downloadedText = response;

}

using System.Net;using System.Threading.Tasks;...

// Create the HttpClientHttpClient httpClient = new HttpClient();httpClient.DefaultRequestHeaders.Add("Accept", "application/json");

// Make the callHttpResponseMessage response = await httpClient.GetAsync(

"http://services.odata.org/Northwind/Northwind.svc/Suppliers");

response.EnsureSuccessStatusCode(); // Throws exception if bad HTTP status code

string responseBodyAsText = await response.Content.ReadAsStringAsync();

Mobile devices are often connected to poor quality network connections

Best chance of success in network data transfers achieved by:

Avoid transferring redundant data

Design your protocol to only transfer precisely the data you need and no more

Wire Serialization Format Size in Bytes

ODATA XML 73786

ODATA JSON 34030

JSON ‘Lite’ 15540

JSON ‘Lite’ GZip 8680

http://sharpziplib.com/

http://sharpcompress.codeplex.com/

var request = HttpWebRequest.Create("http://yourPC/Service.svc/Suppliers") as HttpWebRequest;

request.Accept = "application/json";

request.Method = HttpMethod.Get;

request.Headers["Accept-Encoding"] = "gzip";

HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync();

// Read the response into a Stream object.

System.IO.Stream stream;

stream = new GZipInputStream(response.GetResponseStream());

else

stream = response.GetResponseStream();

string data;

using (var reader = new System.IO.StreamReader(stream))

{

data = reader.ReadToEnd();

}

stream.Close();

private void PhoneApplicationPage_Loaded(object sender, RoutedEventArgs e){

var request = HttpWebRequest.Create("http://myServer:15500/NorthwindDataService.svc/Suppliers") as HttpWebRequest;

request.Credentials = new Credentials("username", "password"); // override allows domain to be specified

request.Accept = "application/json;odata=verbose";

request.BeginGetResponse(new AsyncCallback(GotResponse), request);}

Provide your own UI to request the credentials from the user

If you store the credentials, encrypt them using the ProtectedData class

private void StoreCredentials(){

// Convert the username and password to a byte[].byte[] secretByte = Encoding.UTF8.GetBytes(TBusername.Text + "||" + TBpassword.Text);

// Encrypt the username by using the Protect() method.byte[] protectedSecretByte = ProtectedData.Protect(secretByte, null);

// Create a file in the application's isolated storage.IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForApplication();IsolatedStorageFileStream writestream =

new IsolatedStorageFileStream(FilePath, System.IO.FileMode.Create, System.IO.FileAccess.Write, file);

// Write data to the file.Stream writer = new StreamWriter(writestream).BaseStream;writer.Write(protectedSecretByte, 0, protectedSecretByte.Length);writer.Close();writestream.Close();

}

// Retrieve the protected data from isolated storage.IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForApplication();IsolatedStorageFileStream readstream =

new IsolatedStorageFileStream(FilePath, System.IO.FileMode.Open, FileAccess.Read, file);

// Read the data from the file.Stream reader = new StreamReader(readstream).BaseStream;byte[] encryptedDataArray = new byte[reader.Length];

reader.Read(encryptedDataArray, 0, encryptedDataArray.Length);reader.Close();readstream.Close();

// Decrypt the data by using the Unprotect method.byte[] clearTextBytes = ProtectedData.Unprotect(encryptedDataArray, null);

// Convert the byte array to string.string data = Encoding.UTF8.GetString(clearTextBytes, 0, clearTextBytes.Length);

http://localhost

http://localhost

C:\Users\yourUsername\Documents\IISExpress\config\applicationhost.config

<sites>

<binding protocol="http" bindingInformation="*:18009:localhost" />

<binding protocol="http" bindingInformation="*:18009:YourPCName" />

YourPCName:18009

netsh advfirewall firewall add rule name="IIS Express (non-SSL)" action=allow protocol=TCP dir=in localport=8080

yourPC

8080

http://msdn.microsoft.com/en-us/library/ms178109(v=VS.100).aspx

Supported on Lumia 520, 620, 625, and 720 with the 'Amber' firmware update

Support coming to 82x, 92x and 1020 with the ‘Black’ update (roll out soon!)

Lumia 1520 comes with the ‘Black’ update

App to device

App to app

// Register for incoming connection requestsPeerFinder.ConnectionRequested += PeerFinder_ConnectionRequested;

// Start advertising ourselves so that our peers can find usPeerFinder.DisplayName = "TicTacToe BT";PeerFinder.Start();

// Register for incoming connection requestsPeerFinder.ConnectionRequested += PeerFinder_ConnectionRequested;

// Start advertising ourselves so that our peers can find usPeerFinder.DisplayName = "TicTacToe BT";PeerFinder.Start();

StreamSocket socket;

async void PeerFinder_ConnectionRequested(object sender, ConnectionRequestedEventArgsargs){

if ( args.PeerInformation.DisplayName == "TicTacToe BT" ){

socket = await PeerFinder.ConnectAsync(args.PeerInformation);PeerFinder.Stop();

}}

Connect devices

Acquire content

Exchange digital objects

ProximityDevice device = ProximityDevice.GetDefault();

// Make sure NFC is supportedif (device != null){

PeerFinder.TriggeredConnectionStateChanged += OnTriggeredConnectionStateChanged;

// Start finding peer apps, while making this app discoverable by peersPeerFinder.Start();

}

ProximityDevice device = ProximityDevice.GetDefault();

// Make sure NFC is supportedif (device != null){

PeerFinder.TriggeredConnectionStateChanged += OnTriggeredConnStateChanged;

// Include the Windows 8 version of our app as possible peerPeerFinder.AlternateIdentities.Add("Windows", "my Win8 appID");// Start finding peer apps, while making this app discoverable by peersPeerFinder.Start();

}

void OnTriggeredConnStateChanged(object sender, TriggeredConnectionStateChangedEventArgs args) {

switch (args.State) {case TriggeredConnectState.Listening: // Connecting as host

break;case TriggeredConnectState.PeerFound: // Proximity gesture is complete – setting up link

break;case TriggeredConnectState.Connecting: // Connecting as a client

break;case TriggeredConnectState.Completed: // Connection completed, get the socket

streamSocket = args.Socket;break;

case TriggeredConnectState.Canceled: // ongoing connection cancelled break;

case TriggeredConnectState.Failed: // Connection was unsuccessfulbreak;

}}

PeerFinder.AllowBluetooth = true;PeerFinder.AllowInfrastructure = true;

Windows.Networking.Proximity.ProximityDevice proximityDevice;

long publishedMessageId = -1;

private void PublishUriButton_Click(object sender, RoutedEventArgs e)

{

if (proximityDevice == null) proximityDevice = ProximityDevice.GetDefault();

// Make sure NFC is supported

if (proximityDevice != null) {

// Stop publishing the current message.

if (publishedMessageId != -1) {

proximityDevice.StopPublishingMessage(publishedMessageId);

}

// Publish the new one

publishedMessageId = proximityDevice.PublishUriMessage(new Uri("zune:navigate?appid=351decc7-ea2f-e011-854c-00237de2db9e"));

}

}

+ runner up prizes

Windows Phone Quiz

WIN £50 In the community area (next to Twilio)

Straight after this session (at 10:05)

Hosted by Windows Phone User Group

http://wpug.net/ @wpug

(store gift card)