WPF 02 TreeViews and Value Converters

效果图

 逻辑代码

    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            foreach(var drive in Directory.GetLogicalDrives())
            {
                var item = new TreeViewItem()
                {
                    Header = drive,
                    Tag = drive
                };
                item.Items.Add(null);
                item.Expanded += Folder_Expanded;
                this.FolderView.Items.Add(item);

            }
        }

        private void Folder_Expanded(object sender, RoutedEventArgs e)
        {
            var item = (TreeViewItem)sender;
            if(item.Items.Count != 1 || item.Items[0] != null)
            {
                return;
            }
            item.Items.Clear();
            var fullPath = (string)item.Tag;
            var files = new List<string>();
            try
            {
                var fs = Directory.GetFiles(fullPath);
                if(fs.Length>0)
                {
                    files.AddRange(fs);
                }
                fs = Directory.GetDirectories(fullPath);
                if (fs.Length > 0)
                {
                    files.AddRange(fs);
                }
            }
            catch { }
            files.ForEach(directoryPath =>
            {
                var subItem = new TreeViewItem()
                {
                    Header = GetFileFolderName(directoryPath),
                    Tag = directoryPath
                };
                subItem.Items.Add(null);
                subItem.Expanded += Folder_Expanded;
                item.Items.Add(subItem);
            });
        }
        public static string GetFileFolderName(string path)
        {
            if(string.IsNullOrEmpty(path))
            {
                return string.Empty;
            }
            var normalizedPath = path.Replace('/', '\\');
            var lastIndex = normalizedPath.LastIndexOf('\\');

            if(lastIndex <0)
            {
                return path;
            }
            return path.Substring(lastIndex + 1);
        }
    }

样式代码

<Window x:Class="Wpf02TreeViews.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Wpf02TreeViews"
        mc:Ignorable="d"
        Loaded="Window_Loaded"
        Title="MainWindow" Height="350" Width="525">
    <StackPanel>
        <TreeView x:Name="FolderView" >
            <TreeView.Resources>
                <Style TargetType="{x:Type TreeViewItem}">
                    <Setter Property="HeaderTemplate">
                        <Setter.Value>
                            <DataTemplate>
                                <StackPanel  Orientation="Horizontal">
                                    <Image Width="20" Margin="3" 
                                               Source="{Binding 
                                                    RelativeSource={RelativeSource
                                                            Mode=FindAncestor,
                                                            AncestorType={x:Type TreeViewItem}},
                                                    Path=Tag,
                                                    Converter={x:Static local:HeaderToImageConverter.Instance}}"></Image>          
                                    <TextBlock VerticalAlignment="Center" Text="{Binding}"></TextBlock>
                                </StackPanel>
                            </DataTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </TreeView.Resources>
        </TreeView>
    </StackPanel>
</Window>