Check out example codes for "check connection c#". It will help you in understanding the concepts better.

Code Example 1

public static bool CheckForInternetConnection()
{
    try
    {
        using (var client = new WebClient())
            using (client.OpenRead("http://google.com/generate_204")) 
                return true; 
    }
    catch
    {
        return false;
    }
}

Code Example 2

System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable()

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