c# - 将数据加载到 ListView (WPF)

Question

我正在尝试制作重复文件检测器(相关问题:Compare adjacent list items)。我的一般结构是这样的:

1. 扫描目录并将每个文件所需的详细信息加载到 DupInfo 对象中
2. 计算任何与另一个文件大小匹配的 CRC
3. 显示任何具有匹配大小和 CRC(以及可选的基本目录)的任何内容，并允许用户检查他们想要删除的内容(既可以手动删除，也可以使用“检查所有第一个重复项”之类的按钮)。
4. 删除所选文件。

我在执行第 3 步时遇到问题。第 1 步和第 2 步中的数据位于 DupInfo 对象列表中。这是类定义。

public class DupInfo
    {
        public string FullName { get; set; }
        public long Size { get; set; }
        public uint? CheckSum { get; set; }
        public string BaseDirectory { get; set; }
        public DupInfo(FileInfo file, Crc32 crc, int level)
        {
            FullName = file.FullName;
            Size = file.Length;
            CheckSum = crc.ComputeChecksum(File.ReadAllBytes(FullName));
            BaseDirectory = FullName.Substring(0,FullName.NthIndexOf("\\",level));
        }
        public DupInfo(FileInfo file, int level)
        {
            FullName = file.FullName;
            Size = file.Length;
            BaseDirectory = FullName.Substring(0, FullName.NthIndexOf("\\", level));
        }

    }

我的问题是:

1. 从自定义类 (DupInfo) 列表将数据加载到 Listview 对象的最佳方法是什么？

2. 如果 Listview 不是显示我的重复集的最佳工具，那么最好的是什么？

Answer 1

我会使用绑定(bind)到 ObservableCollection<DupInfo> 的 DataGrid .

<Window x:Class="DataGridDupInfoStack.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525">
<Grid>
    <DataGrid ItemsSource="{Binding items}">

    </DataGrid>
  </Grid>
</Window>

代码隐藏:

public partial class MainWindow : Window
{
    public ObservableCollection<DupInfo> items { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        items = new ObservableCollection<DupInfo>();

        items.Add(new DupInfo() { BaseDirectory = "Directory1", CheckSum = 0xFF, FullName = "Info1", Size = 100 });
        items.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFE, FullName = "Info2", Size = 150 });
        items.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFD, FullName = "Info3", Size = 200 });
        this.DataContext = this;

    }
}

这是您的 DupInfo 类。我省略了构造函数以更快地处理它。

public class DupInfo
{
    public string FullName { get; set; }
    public long Size { get; set; }
    public uint? CheckSum { get; set; }
    public string BaseDirectory { get; set; }
}

结果:

更新 1:

我们没有可用的 AddRange 但为此定义了一个扩展方法:

public static class ExtensionMethods
{
    public static void AddRange(this ObservableCollection<DupInfo> value, List<DupInfo> list)
    {
        foreach (var dup in list)
            value.Add(dup);
    }
}

这是我们的新版本:

public partial class MainWindow : Window
{
    public ObservableCollection<DupInfo> items { get; set; }

    List<DupInfo> initialList { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        items = new ObservableCollection<DupInfo>();
        initialList = new List<DupInfo>();

        initialList.Add(new DupInfo() { BaseDirectory = "Directory1", CheckSum = 0xFF, FullName = "Info1", Size = 100 });
        initialList.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFE, FullName = "Info2", Size = 150 });
        initialList.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFD, FullName = "Info3", Size = 200 });

        items.AddRange(initialList);

        this.DataContext = this;

    }
}

public static class ExtensionMethods
{
    public static void AddRange(this ObservableCollection<DupInfo> value, List<DupInfo> list)
    {
        foreach (var dup in list)
            value.Add(dup);
    }
}

所以我们从一个列表中加载我们的元素..我们可以根据您的需要在那里使用数组或其他任何东西。

但是如果你改变了我们的引用指向的对象，请注意。在这种情况下，您将必须使用 DependencyProperty 或实现 INotifyPropertyChanged。

您的属性(property)将如下所示:

    public  ObservableCollection<DupInfo> items
    {
        get { return ( ObservableCollection<DupInfo>)GetValue(itemsProperty); }
        set { SetValue(itemsProperty, value); }
    }

    // Using a DependencyProperty as the backing store for items.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty itemsProperty =
        DependencyProperty.Register("items", typeof( ObservableCollection<DupInfo>), typeof(MainWindow), new PropertyMetadata(null));

更新 2:

XAML:

<Window x:Class="DataGridDupInfoStack.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="525">
<Grid>
    <StackPanel>
        <DataGrid ItemsSource="{Binding items}" AutoGenerateColumns="False" CanUserAddRows="False">
            <DataGrid.Columns>
                <DataGridTextColumn Header="Full Name" Binding="{Binding FullName}" />
                <DataGridTextColumn Header="Size" Binding="{Binding Size}" />
                <DataGridTextColumn Header="CheckSum" Binding="{Binding CheckSum}" />
                <DataGridTextColumn Header="BaseDirectory" Binding="{Binding BaseDirectory}" />
                <DataGridTemplateColumn Header="Mark for deletion">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <CheckBox IsChecked="{Binding Path=ToDelete, UpdateSourceTrigger=PropertyChanged}" />
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>
        </DataGrid>
        <Button Content="Delete" Click="btnDelete_Click"/>
    </StackPanel>
</Grid>
</Window>

代码隐藏:

public partial class MainWindow : Window
{


    public ObservableCollection<DupInfo> items
    {
        get { return (ObservableCollection<DupInfo>)GetValue(itemsProperty); }
        set { SetValue(itemsProperty, value); }
    }

    // Using a DependencyProperty as the backing store for items.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty itemsProperty =
        DependencyProperty.Register("items", typeof(ObservableCollection<DupInfo>), typeof(MainWindow), new PropertyMetadata(null));



    List<DupInfo> initialList { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        items = new ObservableCollection<DupInfo>();
        initialList = new List<DupInfo>();

        initialList.Add(new DupInfo() { BaseDirectory = "Directory1", CheckSum = 0xFF, FullName = "Info1", Size = 100 });
        initialList.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFE, FullName = "Info2", Size = 150 });
        initialList.Add(new DupInfo() { BaseDirectory = "Directory2", CheckSum = 0xFD, FullName = "Info3", Size = 200 });

        items.AddRange(initialList);

        this.DataContext = this;
    }


    private void btnDelete_Click(object sender, RoutedEventArgs e)
    {
        foreach (var dup in items.ToList())
        {
            if (dup.ToDelete)
            {
                items.Remove(dup);
            }
        }
    }
}

public static class ExtensionMethods
{
    public static void AddRange(this ObservableCollection<DupInfo> value, List<DupInfo> list)
    {
        foreach (var dup in list)
            value.Add(dup);
    }
}

以及更新后的 DupInfo 类:

public class DupInfo : INotifyPropertyChanged
{
    private bool _ToDelete;

    public bool ToDelete
    {
        get { return _ToDelete; }
        set
        {
            _ToDelete = value;
            PropertyChanged(this, new PropertyChangedEventArgs("ToDelete"));
        }
    }

    public string FullName { get; set; }
    public long Size { get; set; }
    public uint? CheckSum { get; set; }
    public string BaseDirectory { get; set; }

    public event PropertyChangedEventHandler PropertyChanged = delegate { };
}

就是这样。祝你好运!