Question

我已将未来日期，事件名称存储在db（sqlite）

中

我正在从db检索日期，事件并使用listview发布它。

如何计算从数据库和当前日期检索的日期剩余天数。？

然后，我需要在列表视图中显示事件和总天数。

所以方法是：

DatabaseHelperClass.cs

public DaysLeft ReadDaysLeft(int daysid)
    {
        using (var dbConn = new SQLiteConnection(App.DB_Path))
        {
            var data = dbConn.Query<DaysLeft>("select * from DaysLeft where Id = " + daysid).FirstOrDefault();
             System.Diagnostics.Debug.WriteLine("In ReadDaysLeft"+data);
            return data;
        }

    }


public ObservableCollection<DaysLeft> ReadDaysLeft()
    {
        using (var dbConn = new SQLiteConnection(App.DB_Path)) 
        {

            List<DaysLeft> mycollection = dbConn.Table<DaysLeft>().ToList<DaysLeft>();
            System.Diagnostics.Debug.WriteLine("In ReadDaysLeftCollection"+mycollection);

            ObservableCollection<DaysLeft> dayslist = new ObservableCollection<DaysLeft>(mycollection);
            System.Diagnostics.Debug.WriteLine("In ReadDaysLeftCollection" + dayslist);
            return dayslist;

        }
    }

ReadALLData.cs

 public class ReadAllData
 {
    DatabaseHelperClass dbHelper = new DatabaseHelperClass();
    public ObservableCollection<DaysLeft> GetAllDays()
    {
        System.Diagnostics.Debug.WriteLine("In GetAllDays");
        return dbHelper.ReadDaysLeft();
    }
}

BasicPage.cs

  private void AddDataToListView(object sender, RoutedEventArgs e)
    {
        ReadAllData alldata = new ReadAllData();
        DB_DaysLeft = alldata.GetAllDays();     

        DaysLeftListView.ItemsSource = DB_DaysLeft.OrderByDescending(i => i.Id).ToList();


    }

我根据您的建议编辑了..添加到两个对象，如

 List<int> daysleft { get; set; }
    string events;

 private void AddDataToListView(object sender, RoutedEventArgs e)
    {
        daysleft = new List<int>();

        ReadAllData alldata = new ReadAllData();
        DB_DaysLeft = alldata.GetAllDays();
        foreach (var Date in DB_DaysLeft)
        {
            DateTime dt = Convert.ToDateTime(Date);

            TimeSpan diff = DateTime.Now - Date.Date;
            int days = (int)Math.Abs(Math.Round(diff.TotalDays));


           //TimeSpan durations= DateTime.Now.Subtract(dt).TotalDays();
            daysleft.Add(days);
        }
        DaysLeftListView.ItemsSource = DB_DaysLeft.OrderByDescending(i => i.Id).ToList();


    }

在BasicPage1.cs

中

     private void DaysLeftListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        int Select_Changed = 0;
        if (DaysLeftListView.SelectedIndex !=-1)
        {
            tempclass selectedDay = DaysLeftListView.SelectedItem as tempclass;
            Frame.Navigate(typeof(EditWindow), Select_Changed = selectedDay.id);
        }
    }

EditOrUpdateWindow.cs

   //from previous page
    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
        Selected_DaysId = Int32.Parse(e.Parameter.ToString());
        daysleft = dbHelp.ReadDaysLeftForEdit(Selected_DaysId);
        var temp_date = daysleft.diff;
        event_date.Date = DateTimeOffset.Parse(daysleft.diff.ToString());
        event_text.Text =   daysleft.myEvent;
       // this.navigationHelper.OnNavigatedTo(e);
    }        




    //To Save into db.
    private void AppBarButton_Click(object sender, RoutedEventArgs e)
    {
        dayleftOfDaysLeft.Date = DateTime.Parse(event_date.Date.ToString());
        dayleftOfDaysLeft.Events = event_text.Text;
        dbHelp.UpdateDays(dayleftOfDaysLeft);
        Frame.Navigate(typeof(BasicPage1));

    }

请帮帮我。谢谢。

Answer 1

它是这样的：

DateTime date1 = DateTime.Now;
DateTime date2 = DateTime.Now.AddDays(30);
int diff = date2.Subtract(date1).TotalDays();

将它绑定到Windows Phone 8.1你需要这样做：

在.cs文件中：

public class AllData
{
   public int diff { get; set; }
   public string myEvent {get;set;}
}

public class RootObject
{
  public List<AllData> dataFromDb { get; set; }
  //all your other code
}

在xaml中：

<ListBox ItemsSource="{Binding dataFromDb }">
    <ListBox.ItemTemplate>
        <DataTemplate >
            <TextBlock Text="{Binding diff}" TextWrapping="Wrap" FontSize="18" />
            <TextBlock Text="{Binding myEvent}" TextWrapping="Wrap" FontSize="18" />
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

如果你还没有完成它，你需要在下载数据之后为页面设置DataContext，就像这样（假设你在页面的代码隐藏文件中进行下载，例如MainPage.xaml.cs中）：

RootObject json = JsonConvert.DeserializeObject<RootObject>(await serverData);
this.DataContext = json;

特定于您的代码，您可以这样做：

public class AllData
{
   public int diff { get; set; }
   public string myEvent {get;set;}
}

public class YourClass{
         List<AllData> daysLeft {get; set;}

         private void AddDataToListView(object sender, RoutedEventArgs e)
            {
                daysleft = new List<AllData>();

                ReadAllData alldata = new ReadAllData();
                DB_DaysLeft = alldata.GetAllDays();
                foreach (var Date in DB_DaysLeft)
                {
                    AllData ad = new AllData();
                    DateTime dt = Convert.ToDateTime(Date);

                    TimeSpan diff = DateTime.Now - Date.Date;
                    int days = (int)Math.Abs(Math.Round(diff.TotalDays));


                   ad.diff = days;
                   ad.myEvent = events;
                    daysleft.Add(ad);
                }
                DaysLeftListView.ItemsSource = DB_DaysLeft.OrderByDescending(i => i.Id).ToList();

     }
}

从db（sqlite）中搜索日期并将其发布到windows phone 8.1中的listview中

1 个答案: