From my WPF, i need to verify internet connection constantly, connection availble set to gree, if no connection, set to red.

From my below code i have the following issue:

1. if there is no internet connection or if i pull the rj45 lan cabel or if i put a static/random ip 192.168.192.90, 255.255.255.0, gateway:192.168.192.90, pref dns:8.8.8.8, the UI is not updating instead it throws various exceptions.

Could you please tell me where am i making the mistake?

private DispatcherTimer BackgroundAsyncTasksTimer;
private void Window_Loaded(object sender, RoutedEventArgs e)
{
   
    BackgroundAsyncTasksTimer = new DispatcherTimer();
    BackgroundAsyncTasksTimer.Interval = TimeSpan.FromMilliseconds(2000);
    BackgroundAsyncTasksTimer.Tick  = BackgroundAsyncTasksTimer_Tick;
    BackgroundAsyncTasksTimer.Start();
}
private async void BackgroundAsyncTasksTimer_Tick(object sender, object e)
{
   
    try
    {
        bool tresult = await IsWebsiteUp_Ping("https://google.com");
        if (tresult)
        {
            this.einternetcoxn.Fill = (SolidColorBrush)new BrushConverter().ConvertFromString("#841c34");
        }
        else
        {
            this.einternetcoxn.Fill = (SolidColorBrush)new BrushConverter().ConvertFromString("#00ff00");
        }
    }
    catch(Exception es)
    {
        Console.WriteLine("Source :{0} ", es.ToString());
   
    }

}
private async Task<bool> IsWebsiteUp_Ping(string url)
{
    try
    {
        Ping ping = new Ping();
        var hostName = new Uri(url).Host;
        byte[] buffer = Encoding.ASCII.GetBytes("samplestring");
        PingReply result = await ping.SendPingAsync(hostName, 500, buffer);
        return result.Status == IPStatus.Success;
    }
    catch (System.Net.Sockets.SocketException e)
    {
        Console.WriteLine("SocketException caught!!!");
        Console.WriteLine("Source : "   e.Source);
        Console.WriteLine("Message : "   e.Message);
        return false;
    }
}

Exceptions:

   à System.Net.Dns.GetHostAddresses(String hostNameOrAddress)
   à System.Net.NetworkInformation.Ping.ContinueAsyncSend(Object state)
   --- Fin de la trace de la pile d'exception interne ---
   à System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   à System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   à System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   à Maintenance.MainWindow.<IsWebsiteUp_Ping>d__19.MoveNext() dans C:\Users\user1\source\repos\Maintenance\Maintenance\MainWindow.xaml.cs:ligne 252
--- Fin de la trace de la pile à partir de l'emplacement précédent au niveau duquel l'exception a été levée ---
   à System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   à System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   à System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   à Maintenance.MainWindow.<BackgroundAsyncTasksTimer_Tick>d__14.MoveNext() dans C:\Users\\user1\source\source\repos\Maintenance\Maintenance\MainWindow.xaml.cs:ligne 152 
Exception thrown: 'System.Net.NetworkInformation.PingException' in mscorlib.dll
Source :System.Net.NetworkInformation.PingException: Une exception s'est produite lors d'une demande PING. ---> System.Net.Sockets.SocketException: Hôte inconnu
   à System.Net.Dns.GetAddrInfo(String name)
   à System.Net.Dns.InternalGetHostByName(String hostName, Boolean includeIPv6)
   à System.Net.Dns.GetHostAddresses(String hostNameOrAddress)
   à System.Net.NetworkInformation.Ping.ContinueAsyncSend(Object state)
   --- Fin de la trace de la pile d'exception interne ---
   à System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   à System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   à System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   à Maintenance.MainWindow.<IsWebsiteUp_Ping>d__19.MoveNext() dans C:\Users\\user1\source\source\repos\Maintenance\Maintenance\MainWindow.xaml.cs:ligne 252
--- Fin de la trace de la pile à partir de l'emplacement précédent au niveau duquel l'exception a été levée ---
   à System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   à System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   à System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()

I tried using the above code but i'm not able to capture or understand where am i doing wrong.

CodePudding user response：

According to the docs, SendPingAsync may throw SocketException or PingException. It's throwing a PingException and your code is catching a SocketException.