C# 引发异常：'；System.TypeLoadException'；UWP后台任务中的未知模块

这个代码给了我一个例外

引发异常：未知模块中的“System.TypeLoadException”

但是，一旦我将

HttpClient

放入

SomeMethodAsync（）

中，它就无法处理上述错误

这个解决方案没有帮助

---

谢谢

我稍微简化了解决方案，删除了

ThreadPoolTimer

，因为我不知道为什么要从代码中使用它。请说明解决方案是否需要此选项

如果

ThreadPoolTimer

是可选的，则可以尝试以下代码：

public sealed class SampleBackgroundTask2 : IBackgroundTask
    {

        EasClientDeviceInformation currentDeviceInfo;

        BackgroundTaskCancellationReason _cancelReason = BackgroundTaskCancellationReason.Abort;

        BackgroundTaskDeferral _deferral = null;

        //
        // The Run method is the entry point of a background task.
        //
        public async void Run(IBackgroundTaskInstance taskInstance)
        {
            currentDeviceInfo = new EasClientDeviceInformation();

            var cost = BackgroundWorkCost.CurrentBackgroundWorkCost;
            var settings = ApplicationData.Current.LocalSettings;
            settings.Values["BackgroundWorkCost2"] = cost.ToString();

            taskInstance.Canceled += new BackgroundTaskCanceledEventHandler(OnCanceled);

            _deferral = taskInstance.GetDeferral();
            await asynchronousAPICall();
            _deferral.Complete(); //calling this only when the API call is complete and the toast notification is shown
        }
        private async Task asynchronousAPICall()
        {
            try
            {
                var httpClient = new HttpClient(new HttpClientHandler());

                string urlPath = (string)ApplicationData.Current.LocalSettings.Values["ServerIPAddress"] + "/Api/Version1/IsUpdatePersonal";

                HttpResponseMessage response = await httpClient.PostAsync(urlPath,
                    new StringContent(JsonConvert.SerializeObject(currentDeviceInfo.Id.ToString()), Encoding.UTF8, "application/json")); // new FormUrlEncodedContent(values)

                response.EnsureSuccessStatusCode();

                if (response.IsSuccessStatusCode)
                {
                    string jsonText = await response.Content.ReadAsStringAsync();
                    var customObj = JsonConvert.DeserializeObject<bool>(jsonText, new JsonSerializerSettings() { TypeNameHandling = TypeNameHandling.All });

                    if (customObj) // Если TRUE  то да надо сообщить пользователю о необходимости обновления
                    {
                        ShowToastNotification("Ttitle", "Message");
                    }
                }
            }
            catch (HttpRequestException ex)
            {
            }
            catch (Exception ex)
            {
            }
            finally
            {
                _deferral.Complete();
            }
        }

        private void OnCanceled(IBackgroundTaskInstance sender, BackgroundTaskCancellationReason reason)
        {
            _cancelReason = reason;
        }
    }

公共密封类SampleBackgroundTask2:IBackgroundTask
{
EasClientDeviceInformation当前设备信息；
BackgroundTaskCancellationReason\u cancelReason=BackgroundTaskCancellationReason.Abort；
BackgroundTaskDeleral _deleral=null；
//
//Run方法是后台任务的入口点。
//
公共异步无效运行（IBackgroundTaskInstance taskInstance）
{
currentDeviceInfo=新的EasClientDeviceInformation（）；
var成本=背景工作成本。当前背景工作成本；
var settings=ApplicationData.Current.LocalSettings；
settings.Values[“BackgroundWorkCost2”]=cost.ToString（）；
taskInstance.Cancelled+=新背景任务CanceledEventHandler（OnCanceled）；
_延迟=taskInstance.getDeleral（）；
等待asynchronousAPICall（）；
_deleral.Complete（）；//仅当API调用完成且显示toast通知时调用此函数
}
专用异步任务asynchronousAPICall（）
{
尝试
{
var httpClient=newhttpclient（newhttpclienthandler（））；
字符串urlPath=（字符串）ApplicationData.Current.LocalSettings.Values[“ServerIPAddress”]+“/Api/Version1/IsUpdatePersonal”；
HttpResponseMessage response=等待httpClient.PostAsync（urlPath，
新建StringContent（JsonConvert.SerializeObject（currentDeviceInfo.Id.ToString（）），Encoding.UTF8，“application/json”）；//新建FormUrlEncodedContent（值）
response.EnsureSuccessStatusCode（）；
if（响应。IsSuccessStatusCode）
{
string jsonText=await response.Content.ReadAsStringAsync（）；
var customObj=JsonConvert.DeserializeObject（jsonText，新的JsonSerializerSettings（）{TypeNameHandling=TypeNameHandling.All}）；
if（customObj）//Сааааааааааааааааа
{
ShowToastNotification（“Ttitle”、“Message”）；
}
}
}
捕获（HttpRequestException-ex）
{
}
捕获（例外情况除外）
{
}
最后
{
_延迟。完成（）；
}
}
已取消私有void（IBackgroundTaskInstance发件人，BackgroundTaskCancellationReason）
{
_取消原因=原因；
}
}

请让我知道这是否适合你

public async void Run(IBackgroundTaskInstance taskInstance)
{
 BackgroundTaskDeferral _deferral = taskInstance.GetDeferral();
 //
 // Start one (or more) async
 // Use the await keyword
 //
 // await SomeMethodAsync();


        var uri = new System.Uri("http://www.bing.com");
        using (var httpClient = new Windows.Web.Http.HttpClient())
        {
            // Always catch network exceptions for async methods
            try
            {
                string result = await httpClient.GetStringAsync(uri);
            }
            catch (Exception ex)
            {
                // Details in ex.Message and ex.HResult.
            }
        }


 _deferral.Complete();
}

public sealed class SampleBackgroundTask2 : IBackgroundTask
    {

        EasClientDeviceInformation currentDeviceInfo;

        BackgroundTaskCancellationReason _cancelReason = BackgroundTaskCancellationReason.Abort;

        BackgroundTaskDeferral _deferral = null;

        //
        // The Run method is the entry point of a background task.
        //
        public async void Run(IBackgroundTaskInstance taskInstance)
        {
            currentDeviceInfo = new EasClientDeviceInformation();

            var cost = BackgroundWorkCost.CurrentBackgroundWorkCost;
            var settings = ApplicationData.Current.LocalSettings;
            settings.Values["BackgroundWorkCost2"] = cost.ToString();

            taskInstance.Canceled += new BackgroundTaskCanceledEventHandler(OnCanceled);

            _deferral = taskInstance.GetDeferral();
            await asynchronousAPICall();
            _deferral.Complete(); //calling this only when the API call is complete and the toast notification is shown
        }
        private async Task asynchronousAPICall()
        {
            try
            {
                var httpClient = new HttpClient(new HttpClientHandler());

                string urlPath = (string)ApplicationData.Current.LocalSettings.Values["ServerIPAddress"] + "/Api/Version1/IsUpdatePersonal";

                HttpResponseMessage response = await httpClient.PostAsync(urlPath,
                    new StringContent(JsonConvert.SerializeObject(currentDeviceInfo.Id.ToString()), Encoding.UTF8, "application/json")); // new FormUrlEncodedContent(values)

                response.EnsureSuccessStatusCode();

                if (response.IsSuccessStatusCode)
                {
                    string jsonText = await response.Content.ReadAsStringAsync();
                    var customObj = JsonConvert.DeserializeObject<bool>(jsonText, new JsonSerializerSettings() { TypeNameHandling = TypeNameHandling.All });

                    if (customObj) // Если TRUE  то да надо сообщить пользователю о необходимости обновления
                    {
                        ShowToastNotification("Ttitle", "Message");
                    }
                }
            }
            catch (HttpRequestException ex)
            {
            }
            catch (Exception ex)
            {
            }
            finally
            {
                _deferral.Complete();
            }
        }

        private void OnCanceled(IBackgroundTaskInstance sender, BackgroundTaskCancellationReason reason)
        {
            _cancelReason = reason;
        }
    }