PeerFinder.DiscoveryData Property

public:
 static property IBuffer ^ DiscoveryData { IBuffer ^ get(); void set(IBuffer ^ value); };

static IBuffer DiscoveryData();

static void DiscoveryData(IBuffer value);

public static IBuffer DiscoveryData { get; set; }

var iBuffer = PeerFinder.discoveryData;
PeerFinder.discoveryData = iBuffer;

Public Shared Property DiscoveryData As IBuffer

Property Value

User or device data to include during device discovery. Must be less than 32 bytes.

Windows requirements

Examples

// Default to the peer role.
Windows.Networking.Proximity.PeerRole appRole = Windows.Networking.Proximity.PeerRole.Peer;
bool launchedByTap = false;

protected override void OnNavigatedTo(NavigationEventArgs e)
{
    LaunchActivatedEventArgs launchArgs = e.Parameter as LaunchActivatedEventArgs;

    if (launchArgs.Arguments.Contains("Windows.Networking.Proximity.PeerFinder:StreamSocket"))
    {
        launchedByTap = true;

        if (launchArgs.Arguments.Contains("Role=Host"))
        {
            appRole = Windows.Networking.Proximity.PeerRole.Host;
        }
        else if (launchArgs.Arguments.Contains("Role=Client"))
        {
            appRole = Windows.Networking.Proximity.PeerRole.Client;
        }
        else
        {
            appRole = Windows.Networking.Proximity.PeerRole.Peer;
        }
    }
}

bool started = false;

// Click event for "Advertise" button.
void AdvertiseForPeers(object sender, RoutedEventArgs e)
{
    if (!started)
    {
        Windows.Networking.Proximity.PeerFinder.DisplayName = DisplayNameTextBox.Text;

        if ((Windows.Networking.Proximity.PeerFinder.SupportedDiscoveryTypes &
             Windows.Networking.Proximity.PeerDiscoveryTypes.Triggered) ==
             Windows.Networking.Proximity.PeerDiscoveryTypes.Triggered)
        {
            Windows.Networking.Proximity.PeerFinder.TriggeredConnectionStateChanged +=
                TriggeredConnectionStateChanged;

            WriteMessageText("You can tap to connect a peer device that is " +
                             "also advertising for a connection.\n");
        }
        else
        {
            WriteMessageText("Tap to connect is not supported.\n");
        }

        if ((Windows.Networking.Proximity.PeerFinder.SupportedDiscoveryTypes &
             Windows.Networking.Proximity.PeerDiscoveryTypes.Browse) !=
             Windows.Networking.Proximity.PeerDiscoveryTypes.Browse)
        {
            WriteMessageText("Peer discovery using Wi-Fi Direct is not supported.\n");
        }

        // Set the peer role selected by the user.  
        if (launchedByTap)
        {
            Windows.Networking.Proximity.PeerFinder.Role = appRole;
        }
        else
        {
            switch (GetRoleFromUser())
            {
                case "Peer":
                    Windows.Networking.Proximity.PeerFinder.Role =
                        Windows.Networking.Proximity.PeerRole.Peer;
                    break;
                case "Host":
                    Windows.Networking.Proximity.PeerFinder.Role =
                        Windows.Networking.Proximity.PeerRole.Host;
                    break;
                case "Client":
                    Windows.Networking.Proximity.PeerFinder.Role =
                        Windows.Networking.Proximity.PeerRole.Client;
                    break;
            }
        }

        // Set discoveryData property with user supplied text. 
        var discData = GetDiscoveryDataFromUser();
        var writer = new Windows.Storage.Streams.DataWriter(
            new Windows.Storage.Streams.InMemoryRandomAccessStream());
        writer.WriteString(discData);
        Windows.Networking.Proximity.PeerFinder.DiscoveryData =
            writer.DetachBuffer();

        Windows.Networking.Proximity.PeerFinder.Start();
        started = true;
    }
}

// Write a message to MessageBlock on the UI thread.
private Windows.UI.Core.CoreDispatcher messageDispatcher = Window.Current.CoreWindow.Dispatcher;
async private void WriteMessageText(string message, bool overwrite = false)
{
    await messageDispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
        () =>
        {
            if (overwrite)
                MessageBlock.Text = message;
            else
                MessageBlock.Text += message;
        });
}

See also

• Proximity and Tapping (C#/VB/C++)
• Proximity sample