How to verify is there is a good internet connection in C#?

Question

I am trying to create a Windows Store App, that performs several avtivities that requires internet connectivity. My code handles a no internet connectivity by storing data in a temporary SQLite DB, but only when there is no internet connection. Something like this:

    // C#
    public bool isInternetConnected()
    {

        ConnectionProfile conn = NetworkInformation.GetInternetConnectionProfile();
        bool isInternet = conn != null && conn.GetNetworkConnectivityLevel() == NetworkConnectivityLevel.InternetAccess;
        return isInternet;
    }

Now, my problem is when I have a bad internet connection. My task will timeout, I will either have to handle the timeout or modify this method.

Does anybody has a good way to handle this????

Answer 1

Try this: If the result is between 40 ~ 120, the latency is good, and your connection is good :)

Usage:

PingTimeAverage("stackoverflow.com", 4);

Implementation:

public static double PingTimeAverage(string host, int echoNum)
{
    long totalTime = 0;
    int timeout = 120;
    Ping pingSender = new Ping ();

    for (int i = 0; i < echoNum; i++)
    { 
        PingReply reply = pingSender.Send (host, timeout);
        if (reply.Status == IPStatus.Success)
        {
            totalTime += reply.RoundtripTime;
        }
    }
    return totalTime / echoNum;
}

Answer 2

If you use a try statement with an exception it should be able to handle the operation when there is no internet connection. Not having the internet connection could be the exception.

try 
{
    // Do not initialize this variable here.
}
catch
{
}

I think using try-catch in this case is probably going to be the most efficient way to handle if internet breaks.

Answer 3

I'd try this and perhaps call it repeatedly and for multiple test URIs:

public static async Task<bool> CheckIfWebConnectionIsGoodAsync(TimeSpan? minResponseTime, Uri testUri)
{
    if (minResponseTime == null)
    {
        minResponseTime = TimeSpan.FromSeconds(0.3);
    }

    if (testUri == null)
    {
        testUri = new Uri("http://www.google.com");
    }

    var client = new HttpClient();
    var cts = new CancellationTokenSource(minResponseTime.Value);

    try
    {
        var task = client.GetAsync(testUri).AsTask(cts.Token);
        await task;
        if (task.IsCanceled)
            return false;
        return true;
    }
    catch (Exception)
    {
        return false;
    }
}