"arg_targetinvocationexception" - 如何确定原因？

Question

enter image description here

private HttpClient CreateHttpClient(string UserToken = "")
            {
                HttpClientHandler handler = new HttpClientHandler();
                HttpClient httpClient = new HttpClient();
                httpClient.Timeout = TimeSpan.FromSeconds(20);
                httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));         
                httpClient.DefaultRequestHeaders.Add(AppConfig.HeaderKey_AppToken, AppConfig.HeaderValue_AppToken);
              
                if (!string.IsNullOrEmpty(UserToken))
                {
                    httpClient.DefaultRequestHeaders.Add("UserToken", UserToken);
                }
                return httpClient;
            }

异常发生在“HttpClient httpClient = new HttpClient(); httpClient.Timeout = TimeSpan.FromSeconds(20);"这一行

我附上了我所面临的确切“arg_targetinvocationexception”问题的图片 check.I 我正在使用 MAUI 和 VS2022 上的最新预览版。当我访问这个功能时，我正面临“arg_targetinvocationexception”本期

主要是当我运行应用程序处于调试模式时它正在工作 fine.But 当我运行应用程序处于实时模式时显示此错误附件图像中显示一个警告框。

private async Task SendOTPClicked()
        {
            try
            {
                var networkFlag = Common.Instance.IsNetworkConnected();
                if (networkFlag)
                {
                    CustomProgressDialog.Instance.ShowLoading(AppResources.Sending_lbl);
                    string url = $"{AppConfig.ApiBaseUrl}{AppConfig.ApiKeypoints_sendotp}";
                    string phonenumber = CountryCode.Replace("+", "") + PhoneNumber;
                    string ApiUrl = $"{url}{phonenumber}";
                    var response = await RequestProviderService.Instance.PostAsync<ResponseViewModel<string>>(ApiUrl, phonenumber, "", AppConfig.TenantId_Value, "", null);
                    if (response != null)
                    {
                        if (response.Status)
                        {
                         
                               await UserDialogs.Instance.AlertAsync(response.Message, AppResources.Title_Success, AppResources.Ok_Flag);
                         
                            
                            await App.Current.MainPage.Navigation.PushAsync(new EnterOTPView(CountryCode.Replace("+", "") + _phonenumber, User));
                            CustomProgressDialog.Instance.HideLoading();                
                        }
                        else
                        {
                            string errorMessage = string.IsNullOrEmpty(response.ErrorMessage) ? response.Message : response.ErrorMessage;
                            CustomProgressDialog.Instance.HideLoading();
                            if (!string.IsNullOrEmpty(errorMessage))
                            {
                                  await UserDialogs.Instance.AlertAsync(errorMessage, AppResources.Alert_Label, AppResources.Ok_Flag);
                            }
                        }
                    }
                    else
                    {
                        CustomProgressDialog.Instance.HideLoading();                        
                    }                        
                }
                else
                {
                  
                        await UserDialogs.Instance.AlertAsync(AppResources.NetworkError_CheckConnection, AppResources.Alert_Label, AppResources.Ok_Flag);
                 
                    
                }
            }
            catch (System.Exception ex)
            {
                CustomProgressDialog.Instance.HideLoading();
            }

        }

Answer 1

我已经使用“AndroidMessageHandler()”并解决了我的问题

 if(Device.RuntimePlatform == Device.Android)
                    {
                        //HttpClientHandler handler = new HttpClientHandler();
                        var Msghandler = new Xamarin.Android.Net.AndroidMessageHandler();
                        httpClient = new HttpClient(Msghandler); 
                    }
                    else
                    {
                        httpClient = new HttpClient();
                    }

"arg_targetinvocationexception" - 如何确定原因？

"arg_targetinvocationexception" - how determine the cause?

xamarin.android

xamarin

xamarin.forms

maui