PeerFinder.CreateWatcher Méthode
Définition
Important
Certaines informations portent sur la préversion du produit qui est susceptible d’être en grande partie modifiée avant sa publication. Microsoft exclut toute garantie, expresse ou implicite, concernant les informations fournies ici.
Crée une instance d’un objet PeerWatcher pour la découverte dynamique des applications homologues.
public:
static PeerWatcher ^ CreateWatcher();
static PeerWatcher CreateWatcher();
public static PeerWatcher CreateWatcher();
function createWatcher()
Public Shared Function CreateWatcher () As PeerWatcher
Retours
Instance d’un objet PeerWatcher pour la découverte dynamique d’applications homologues.
Configuration requise pour Windows
Fonctionnalités de l’application |
proximity
|
Remarques
Vous devez d’abord appeler la méthode Start avant d’appeler la méthode CreateWatcher.
Si vous appelez la méthode CreateWatcher plusieurs fois, vous recevrez une référence au même instance PeerWatcher.
private PeerWatcher _peerWatcher;
private bool _peerWatcherIsRunning = false;
private bool _peerFinderStarted = false;
// The list of peers discovered by the PeerWatcher.
ObservableCollection<PeerInformation> _discoveredPeers = new ObservableCollection<PeerInformation>();
void PeerFinder_StartPeerWatcher(object sender, RoutedEventArgs e)
{
if (!_peerFinderStarted)
{
// PeerFinder must be started first.
return;
}
if (_peerWatcherIsRunning)
{
// PeerWatcher is already running.
return;
}
try
{
if (_peerWatcher == null)
{
_peerWatcher = PeerFinder.CreateWatcher();
// Add PeerWatcher event handlers. Only add handlers once.
_peerWatcher.Added += PeerWatcher_Added;
_peerWatcher.Removed += PeerWatcher_Removed;
_peerWatcher.Updated += PeerWatcher_Updated;
_peerWatcher.EnumerationCompleted += PeerWatcher_EnumerationCompleted;
_peerWatcher.Stopped += PeerWatcher_Stopped;
}
// Empty the list of discovered peers.
_discoveredPeers.Clear();
// Start the PeerWatcher.
_peerWatcher.Start();
_peerWatcherIsRunning = true;
}
catch (Exception ex)
{
// Exceptions can occur if PeerWatcher.Start is called multiple times or
// PeerWatcher.Start is called the PeerWatcher is stopping.
}
}
protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
if (_peerWatcher != null)
{
// Remove event handlers.
_peerWatcher.Added -= PeerWatcher_Added;
_peerWatcher.Removed -= PeerWatcher_Removed;
_peerWatcher.Updated -= PeerWatcher_Updated;
_peerWatcher.EnumerationCompleted -= PeerWatcher_EnumerationCompleted;
_peerWatcher.Stopped -= PeerWatcher_Stopped;
_peerWatcher = null;
}
}