WPF之TreeView

介绍：

TreeView`控件用于显示分层结构的数据，如文件夹结构、组织结构图等。它允许用户通过展开和折叠节点来查看和隐藏其子节点。与ListBox和ListView一样，它也是继承自ItemsControl，这意味着它可以包含任何类型的对象的集合。

基本使用：

<TreeView Name="treeView">
    <TreeViewItem Header="根节点1"/>
    <TreeViewItem Header="根节点2">
        <TreeViewItem Header="子节点"/>
    </TreeViewItem>
</TreeView>

代码动态添加或删除节点：

            TreeViewItem rootNode = new TreeViewItem { Header = "新节点" };
            treeView.Items.Add(rootNode);  // 添加根节点
            rootNode.IsExpanded = true;// 展开节点
            rootNode.Items.Add(new TreeViewItem { Header = "子节点" });  // 添加子节点

数据绑定：

通过 HierarchicalDataTemplate 绑定分层数据，支持无限级嵌套：

        <TreeView x:Name="treeView" Width="600" Height="800" SelectedItemChanged="treeView_SelectedItemChanged">
            <TreeView.ItemTemplate>
                <HierarchicalDataTemplate ItemsSource="{Binding Children}">
                    <TextBlock Text="{Binding Name}"/>
                </HierarchicalDataTemplate>
            </TreeView.ItemTemplate>
        </TreeView>

public jianshuWin()
{
    InitializeComponent();

    List<User> users = AddUser("根节点", 5);
    var item = users[0];
    item.Children = AddUser("子节点", 3);
    var item2 = item.Children[1];
    item2.Children = AddUser("最后节点", 2);
    this.treeView.ItemsSource = users;


}
private List<User> AddUser(string nameStr, int count)
{
    List<User> list = new List<User>();
    for (int i = 0; i < count; i++)
    {
        var user = new User();
        user.Name = nameStr + i;
        list.Add(user);
    }
    return list;
}
public class User
{
    public string? Name { get; set; }
    public List<User>? Children { get; set; }

}

事件处理

        private void treeView_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
        {
            var selectedItem = e.NewValue as User;
            MessageBox.Show($"You selected: {selectedItem?.Name}");

            //var selectedItem = (User)this.treeView.SelectedItem;
            //MessageBox.Show($"You selected: {selectedItem?.Name}");
        }