如何在WPF层级TreeView中获取NodeTitle并修改文本？

方法一：通过可视化树查找控件 #

先实现一个通用的可视化树子控件查找方法，用来定位模板内的NodeTitle TextBlock：

private T FindVisualChild<T>(DependencyObject parent, string name) where T : FrameworkElement
{
    for (int i = 0; i < VisualTreeHelper.GetChildrenCount(parent); i++)
    {
        DependencyObject child = VisualTreeHelper.GetChild(parent, i);
        if (child != null && child is T childElement && childElement.Name == name)
        {
            return childElement;
        }
        else
        {
            T result = FindVisualChild<T>(child, name);
            if (result != null)
                return result;
        }
    }
    return null;
}

然后在右键事件中调用该方法获取并修改TextBlock：

private void FavpritesTreeView_PreviewMouseRightButtonUp(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
    DependencyObject obj = e.OriginalSource as DependencyObject;
    TreeViewItem treeViewItem = GetDependencyObjectFromVisualTree(obj, typeof(TreeViewItem)) as TreeViewItem;

    if (treeViewItem != null)
    {
        // 查找模板内的NodeTitle TextBlock
        TextBlock nodeTitle = FindVisualChild<TextBlock>(treeViewItem, "NodeTitle");
        if (nodeTitle != null)
        {
            // 修改文本内容
            nodeTitle.Text = "自定义新标题";
        }
    }
}

方法二：修改绑定的数据源（推荐） #

WPF基于数据驱动，直接修改绑定的Node对象属性是更符合设计理念的方式，无需操作UI控件：

1. 确保Node类实现INotifyPropertyChanged接口，保证属性变化时UI自动更新：

public class Node : INotifyPropertyChanged
{
    private string _title;
    public string Title
    {
        get => _title;
        set
        {
            if (_title != value)
            {
                _title = value;
                OnPropertyChanged(nameof(Title));
            }
        }
    }

    public ObservableCollection<Node> Items { get; set; } = new ObservableCollection<Node>();
    public string ImagePath { get; set; }

    public event PropertyChangedEventHandler PropertyChanged;

    protected void OnPropertyChanged(string propertyName)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

2. 在右键事件中直接修改Node对象的Title属性：

private void FavpritesTreeView_PreviewMouseRightButtonUp(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
    DependencyObject obj = e.OriginalSource as DependencyObject;
    TreeViewItem treeViewItem = GetDependencyObjectFromVisualTree(obj, typeof(TreeViewItem)) as TreeViewItem;

    if (treeViewItem != null && treeViewItem.DataContext is Node node)
    {
        // 修改绑定的Title属性，UI会自动更新
        node.Title = "自定义新标题";
    }
}

注意：方法二更稳定，避免了直接操作UI控件带来的耦合问题，尤其是在模板重新加载时不会失效。

内容的提问来源于stack exchange，提问作者Igor Goblin