參考資料:

 https://msdn.microsoft.com/zh-tw/library/bb613579(v=vs.110).aspx

 public static bool IsNetworkAvailable()
        {
            bool isAvailable = false;

            var profile = NetworkInformation.GetInternetConnectionProfile();

            if (profile == null) {
                return false;
            }

            var connections = profile.GetNetworkConnectivityLevel();

            switch (connections) {
                case NetworkConnectivityLevel.ConstrainedInternetAccess:
                case NetworkConnectivityLevel.InternetAccess:

                    isAvailable = true;

                    break;
                case NetworkConnectivityLevel.LocalAccess:
                case NetworkConnectivityLevel.None:

                    isAvailable = false;

                    break;

                default:
                    break;
            }

            return isAvailable;
        }

 

// Get

HttpWebRequest httpWebRequest = WebRequest.CreateHttp(url);
httpWebRequest.Method = HttpMethod.Get.Method;

httpWebRequest.Headers = new WebHeaderCollection();
httpWebRequest.Headers["header"] = header;


    using (var response = await httpWebRequest.GetResponseAsync()) {

        using (Stream stream = response.GetResponseStream()) {

            using (StreamReader reader = new StreamReader(stream)) {

                // Read the content.
                result = reader.ReadToEnd();
            }
        }
    }

參數設定

1.打勾

使用Dispatcher.invoke 包覆出現 Exception的程式碼

　　DataTrigger 如果Binding實值型別，bool、int或string(使用等於"字串"給值的方式)，

　　第二次想要再觸發的時候，只變更Field，並使用OnNotifyPropertyChange(propertyName)，進行通知UI，且Get也有正常的被呼叫，但DataTrigger 並不會被觸發，這個問題卡了兩天，後來偶然的改成Binding 別的物件，意外發現這個問題!

u  UserControl.xaml

強大的降刷教學 http://www.wpxap.com/thread-538832-1-1.html