当输入用户名和密码时，UWP崩溃

Question

这是我的第一篇文章。我会尝试获取所有相关信息。我正在为我的BS Capstone课程开发UWP。我有一个主页让用户可以选择输入用户名和密码并登录，或输入用户名和密码并注册，以便他们能够登录。我在那里有一些例外用户没有注册，对话框会通知他们需要注册。 问题是当我输入用户名和密码时，我知道该用户名和密码未注册，应用程序崩溃。 我正在使用VS 2015和Azure SQL数据库。唯一的线索我有什么错误的是输出显示以下消息。 抛出异常： 'System.Net.Http.HttpRequestException' 在mscorlib.ni.dll

而且，我在App.Xaml.cs标签连接字符串

public static MobileServiceClient MobileService = new 
MobileServiceClient("http://tale-server1.database.windows.net"); 

最后，当试图要注册一个新用户，Catch发生以下异常：

catch (Exception em) 
     { 
      var dialog = new MessageDialog("An Error Occured: " + 
em.Message); 
      await dialog.ShowAsync(); 
     } 

我的主页代码如下。

using System; 
using System.Collections.Generic; 
using System.IO; 
using System.Linq; 
using System.Runtime.InteropServices.WindowsRuntime; 
using Windows.Foundation; 
using Windows.Foundation.Collections; 
using Windows.UI.Xaml; 
using Windows.UI.Xaml.Controls; 
using Windows.UI.Xaml.Controls.Primitives; 
using Windows.UI.Xaml.Data; 
using Windows.UI.Xaml.Input; 
using Windows.UI.Xaml.Media; 
using Windows.UI.Xaml.Navigation; 
using Microsoft.WindowsAzure.MobileServices; 
using System.Threading.Tasks; 
using Windows.UI.Popups; 
using Windows.Storage; 
using System.Net.Http; 
using Newtonsoft.Json; 
using SQLite; 
using SQLite.Net; 
using SQLite.Net.Async; 
using Microsoft.WindowsAzure.MobileServices.Sync; 
using Microsoft.WindowsAzure.MobileServices.SQLiteStore; 
using SQLitePCL; 


// The Blank Page item template is documented at 
http://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409 

namespace TALE_Capstone 
{ 
/// <summary> 
/// An empty page that can be used on its own or navigated to within a 
Frame. 
/// </summary> 
public sealed partial class MainPage : Page 
{ 
    public MainPage() 
    { 
     this.InitializeComponent(); 
    } 

    public int IsAuth { get; set; } 

    //[DataTable("User_Cred")] 
    public class User_Cred 
    { 
     public string id { get; set; } 
     public string userName { get; set; } 
     public string Password { get; set; } 

    } 

    private IMobileServiceSyncTable<User_Cred> todoGetTable = 
App.MobileService.GetSyncTable<User_Cred>(); 



    private async Task InitLocalStoreAsync() 
    { 
     if (!App.MobileService.SyncContext.IsInitialized) 
     { 
      var store = new MobileServiceSQLiteStore("Tale-DB"); 
      store.DefineTable<User_Cred>(); 
      await App.MobileService.SyncContext.InitializeAsync(store); 
     } 
     await SyncAsync(); 
    } 

    private async Task SyncAsync() 
    { 
     await App.MobileService.SyncContext.PushAsync(); 
     await todoGetTable.PullAsync("User_Cred", 
todoGetTable.CreateQuery()); 
    } 



    async public void submitAuthBtn_Click(object sender, RoutedEventArgs e) 
    { 
     await InitLocalStoreAsync(); 

     GetAuthentication(); 

    } 

    async public void GetAuthentication() 
    { 
     try 
     { 

      //IMobileServiceTable<User_Cred> todoTable = App.MobileService.GetTable<User_Cred>(); 

      List<User_Cred> items = await todoGetTable 
       .Where(User_Cred => User_Cred.userName == UserNameEnter.Text) 
       .ToListAsync(); 

      IsAuth = items.Count(); 

      // Return a List UI control value back to the form 

      foreach (var value in items) 
      { 
       var dialog = new MessageDialog("Welcome Back " + value.userName); 
       await dialog.ShowAsync(); 
      } 


      if (IsAuth > 0) 
      { 
       var dialog = new MessageDialog("You are Authenticated"); 
       await dialog.ShowAsync(); 

      } 
      else 
      { 
       var dialog = new MessageDialog(" Account Does Not Exist, please Register to get Started."); 
       await dialog.ShowAsync(); 
      } 
     } 
     catch (Exception em) 
     { 
      var dialog = new MessageDialog("An Error Occured: " + em.Message); 
      await dialog.ShowAsync(); 
     } 
    } 

    async private void submitAuthBtn_Copy_Click(object sender, RoutedEventArgs e) 
    { 
     try 
     { 
      User_Cred itemReg = new User_Cred 
      { 
       userName = UserNameEnter.Text, 
       Password = PWEnter.Text 
      }; 
      await App.MobileService.GetTable<User_Cred>().InsertAsync(itemReg); 
      var dialog = new MessageDialog("Thank you for Registering! Lets begin"); 
      await dialog.ShowAsync(); 
     } 
     catch (Exception em) 
     { 
      var dialog = new MessageDialog("An Error Occured: " + em.Message); 
      await dialog.ShowAsync(); 
     } 
    } 



} 
} 

任何帮助，将不胜感激！

康拉德

Answer 1

根据你的描述，我认为你是连接你与Azure的移动应用后端和Azure的SQL数据库用于存储数据UWP应用。据我所知，中MobileServiceClient初始化看起来像如下：

MobileServiceClient MobileService = new MobileServiceClient("https://{your-appname}.azurewebsites.net"); 

我建议你可以按照这个tutorial并下载sample client project来检查这个问题。此外，您可以利用fiddler并在将您的uwp应用程序连接到azure移动应用程序以获取详细的错误消息时收集网络跟踪，然后您可以缩小此问题，或者您可以使用详细的错误更新您的问题，以便我们找到此问题。