GetNetworkInfo

DetectNetwork.cs

using Android.Net;

private void DetectNetwork()
{
    ConnectivityManager connectivityManager = (ConnectivityManager)GetSystemService(ConnectivityService);
    NetworkInfo activeConnection = connectivityManager.ActiveNetworkInfo;

    bool isOnline = (activeConnection != null) && activeConnection.IsConnected;

    if (isOnline)
    {
        // Networkのタイプを表示
        NetworkInfo.State activeState = activeConnection.GetState();
        System.Diagnostics.Debug.WriteLine(activeConnection.TypeName);

        // 全接続を取得して、それぞれの接続状態を確認
        // GetAllNetworks()は5.0以上でそれ以前はgetAllNetworkInfo()を使用
        if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.Lollipop)
        {
            Network[] allNetworks = connectivityManager.GetAllNetworks();
            foreach (var item in allNetworks)
            {
                NetworkInfo info = connectivityManager.GetNetworkInfo(item);
                var connect = info.IsConnectedOrConnecting ? "cennected" : "disconnected";
                System.Diagnostics.Debug.WriteLine($"{info.TypeName} is {connect}");
            }
        }
        else
        {
            NetworkInfo[] allNetworks = connectivityManager.GetAllNetworkInfo();
            foreach (var item in allNetworks)
            {
                var connect = item.IsConnectedOrConnecting ? "cennected" : "disconnected";
                System.Diagnostics.Debug.WriteLine($"{item.TypeName} is {connect}");
            }
        }
    }
}