Question

这是我的班级：

 [Table]
public class ListData : INotifyPropertyChanged, INotifyPropertyChanging
{
    private int _id;
    [Column(IsPrimaryKey = true, IsDbGenerated = true, DbType = "INT NOT NULL Identity", CanBeNull = false, AutoSync = AutoSync.OnInsert)]
    public int Id
    {
        get
        {
            return _id;
        }
        set
        {
            if (_id != value)
            {
                OnPropertyChanging("Id");
                _id = value;
                OnPropertyChanged("Id");
            }
        }
    }

    private string _name;
    [Column()]
    public string Name
    {
        get
        { return _name; }
        set
        {
            if (_name != value)
            {
                OnPropertyChanging("Name");
                _name = value;
                OnPropertyChanged("Name");
            }
        }
    }
    private string _url;
    [Column()]
    public string Url
    {
        get
        {
            return _url;
        }
        set
        {
            if (_url != value)
            {
                OnPropertyChanging("Url");
                _url = value;
                OnPropertyChanged("Url");
            }
        }
    }

    public event PropertyChangingEventHandler PropertyChanging;
    public event PropertyChangedEventHandler PropertyChanged;

    private void OnPropertyChanged(string propertyName)
    {
        if (PropertyChanging != null)
        {
            PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
        }
    }
    private void OnPropertyChanging(string propertyName)
    {
        if (PropertyChanging != null)
        {
            PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
        }
    }
}

public class ListDataContext : DataContext
{
    public static string DBConnectionString = "Data Source=isostore:/ListDataDB.sdf";
    public ListDataContext(string sConnectionString)
        : base(sConnectionString)
    { }
    public Table<ListData> Datas;
}

这是我的xaml（列表框）的一部分：

<ListBox x:Name="listData" Grid.Row="1">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel  Orientation="Horizontal" VerticalAlignment="Center">
                        <TextBlock Text="{Binding Path=Name}" 
                                                   Style="{StaticResource PhoneTextTitle2Style}"
                                                   x:Name="txbName"
                                                   Tap="txbName_Tap">
                        </TextBlock>

                        <Button Tag="{Binding BindsDirectlyToSource=True}" 
                                            Click="Button_Click"  
                                            Content="X" 
                                            BorderBrush="Red" 
                                            Background="Red" 
                                            Foreground="{StaticResource PhoneBackgroundBrush}" 
                                            VerticalAlignment="Top" BorderThickness="0" Width="70" Height="70">
                        </Button>
                    </StackPanel>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>

这是我加载数据的方法：

public void LoadData()
    {
        this.listData.ItemsSource = GetData();
    }

    public ObservableCollection<ListData> GetData()
    {
        List<ListData> listDatas = new List<ListData>();
        using (var db = new ListDataContext(ConnectionString))
        {
            var query = from e in db.Datas
                        select e;
            listDatas = query.ToList();
        }

        return new ObservableCollection<ListData>(listDatas);
    }

这就是我删除它们的方式：

private void Button_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                var data = (ListData)((Button)sender).Tag;
                using (var db = new ListDataContext(ConnectionString))
                {
                    var entities = from i in db.Datas
                                 where i.Name == data.Name
                                 select i;
                    var entity = entities.FirstOrDefault();
                    db.Datas.DeleteOnSubmit(entity);
                    db.SubmitChanges();
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

出了什么问题？删除后为什么我的ListBox没有刷新？ ObservableCollection有问题吗？

Answer 1

您正在从数据库中删除它，但我没有看到您再次调用GetData（）的位置，或者从ObservableCollection中删除它。删除后尝试调用GetData，或者至少从集合中手动删除所选项目。

删除项目后，ListBox不刷新

1 个答案: