c# - SQL Server CE WP7 中不出现行

Question

ToDoDataContext

在这里，我为数据库创建了一个上下文。

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Data.Linq;

namespace My_CookBook
{
    public class ToDoDataContext : DataContext
    {
        public static string DBConnectionString = "Data Source=isostore:/kupa.sdf";

        public ToDoDataContext(string connectionString)
            : base(connectionString)
        { }

        public Table<ToDoItem> ToDoItems;
    }
}

ToDoItem

这是项目的模型。

using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.ComponentModel;
using System.Data.Linq.Mapping;

namespace My_CookBook
{
    [Table]
    public class ToDoItem : INotifyPropertyChanged, INotifyPropertyChanging
    {
        // Define ID: private field, public property and database column.
        private int _toDoItemId;

        [Column(IsPrimaryKey=true, IsDbGenerated=true,DbType = "INT NOT NULL Identity", CanBeNull=false, AutoSync= AutoSync.OnInsert)]
        public int ToDoItemId
        {
            get
            {
                return _toDoItemId;
            }
            set
            {
                if (_toDoItemId != value)
                {
                    NotifyPropertyChanging("ToDoItemId");
                    _toDoItemId = value;
                    NotifyPropertyChanged("ToDoItemId");
                }
            }
        }

        /////////////////////////////////////// Nazwa //////////////////////////////////////////

        private string _Name;

        [Column]
        public string Name
        {
            get
            {
                return _Name;
            }
            set
            {
                if (_Name != value)
                {
                    NotifyPropertyChanging("Name");
                    _Name = value;
                    NotifyPropertyChanged("Name");
                }
            }
        }

        /////////////////////////////////////// Autor //////////////////////////////////////////

        private string _Autor;

        [Column]
        public string Autor
        {
            get
            {
                return _Autor;
            }
            set
            {
                if (_Autor != value)
                {
                    NotifyPropertyChanging("Autor");
                    _Autor = value;
                    NotifyPropertyChanged("Autor");
                }
            }
        }


        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        // Used to notify the page that a data context property changed
        private void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

        #endregion

        #region INotifyPropertyChanging Members

        public event PropertyChangingEventHandler PropertyChanging;

        // Used to notify the data context that a data context property is about to change
        private void NotifyPropertyChanging(string propertyName)
        {
            if (PropertyChanging != null)
            {
                PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
            }
        }

        #endregion
    }
}

显示所有

在此页面上应显示行。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Data;
using System.Data.Linq;
using System.Data.Linq.Mapping;
using System.Windows.Media.Imaging;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Tasks;
using System.Collections.ObjectModel;
using System.ComponentModel;

namespace My_CookBook
{
    public partial class show_all : PhoneApplicationPage
    {

        // Data context for the local database
        private ToDoDataContext toDoDB;

        // Define an observable collection property that controls can bind to.
        private ObservableCollection<ToDoItem> _toDoItems;
        public ObservableCollection<ToDoItem> ToDoItems
        {
            get
            {
                return _toDoItems;
            }
            set
            {
                if (_toDoItems != value)
                {
                    _toDoItems = value;
                    NotifyPropertyChanged("ToDoItems");
                }
            }
        }

        // Constructor
        public show_all()
        {
            InitializeComponent();
            // Connect to the database and instantiate data context.
            toDoDB = new ToDoDataContext(ToDoDataContext.DBConnectionString);


            // Define the query to gather all of the to-do items.
            var toDoItemsInDB = from ToDoItem todo in toDoDB.ToDoItems
                                select todo;

            // Execute the query and place the results into a collection.
            ToDoItems = new ObservableCollection<ToDoItem>(toDoItemsInDB);

            toDoDB.SubmitChanges();
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            this.NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
        }

        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        // Used to notify the page that a data context property changed
        private void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

        #endregion

    }
}

显示全部

我使用绑定来检索行。

<Grid x:Name="ContentPanel1" Grid.Row="1" Margin="12,0,12,0">
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto" />
                <RowDefinition Height="Auto" />
            </Grid.RowDefinitions>

            <ListBox x:Name="toDoItemsListBox" ItemsSource="{Binding ToDoItems}" 
                     Grid.Row="0" Margin="12, 0, 12, 0" Width="440">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <Grid HorizontalAlignment="Stretch" Width="440">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="50" />
                                <ColumnDefinition Width="*" />
                                <ColumnDefinition Width="100" />
                            </Grid.ColumnDefinitions>

                            <TextBlock
                                Text="{Binding Path=Name}"
                                FontSize="{StaticResource PhoneFontSizeLarge}"
                                Grid.Column="1"
                                VerticalAlignment="Center"/>
                            <Button
                                Grid.Column="2"
                                x:Name="deleteTaskButton"
                                BorderThickness="0"                                
                                Margin="0">
                                <Image Source="Images/appbar.delete.rest.png"/>
                            </Button>
                        </Grid>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Grid>

添新

在这里，我向数据库添加新行：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Data;
using System.Windows.Media.Imaging;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Tasks;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Data.Linq;
using System.Data.Linq.Mapping;

namespace My_CookBook
{
    public partial class add_new : PhoneApplicationPage
    {
        // Constructor
        public add_new()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            this.NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
        }

        private void slider1_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
        {
            if (slider1 != null)
            {
                slider1.Value = Math.Round(e.NewValue);
                qwe((int)slider1.Value);
            }
        }

        private void qwe(int a)
        {
          stackPanel1.Height = 1250 + a * 159;
          stackPanel2.Height = a * 159;
        }

        private void button3_Click(object sender, RoutedEventArgs e)
        {
            CameraCaptureTask camera = new CameraCaptureTask();
            camera.Show();
            ManipulationCompletedEventArgs photo = new ManipulationCompletedEventArgs();
        }

        private void button2_Click(object sender, RoutedEventArgs e)
        {
            ToDoDataContext toDoDB = new ToDoDataContext(ToDoDataContext.DBConnectionString);
            ToDoItem newToDo = new ToDoItem();
            newToDo.Name = textBox1.Text;
            newToDo.Autor = textBox2.Text;

            toDoDB.ToDoItems.InsertOnSubmit(newToDo);
            toDoDB.SubmitChanges();
            MessageBox.Show("Pomyślnie dodano przepis.");

            this.NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
        }

        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        // Used to notify the page that a data context property changed
        private void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion
    }
}

我的问题是，程序不显示Show all数据库中的任何行（在页面中）。为什么？

在调试器中是好的。我真的不知道出了什么问题。