LINQ:遍历层次结构以检索父层次结构

public class Node
{
    public int Id { get; set; }
    public string Name { get; set; }
    public int ParentId { get; set; }
    public List<Node> Children { get; set; }
}

public static IEnumerable<Node> GetParentHierarchy(Node node, List<Node> nodes)
{
    var parent = nodes.FirstOrDefault(n => n.Id == node.ParentId);
    if (parent != null)
    {
        yield return parent;
        foreach (var ancestor in GetParentHierarchy(parent, nodes))
        {
            yield return ancestor;
        }
    }
}

public static void Main()
{
    List<Node> nodes = new List<Node>
    {
        new Node { Id = 1, Name = "Node 1", ParentId = 0 },
        new Node { Id = 2, Name = "Node 2", ParentId = 1 },
        new Node { Id = 3, Name = "Node 3", ParentId = 2 },
        new Node { Id = 4, Name = "Node 4", ParentId = 3 }
    };

    Node node = nodes.FirstOrDefault(n => n.Id == 4);
    if (node != null)
    {
        var parentHierarchy = GetParentHierarchy(node, nodes);
        foreach (var parent in parentHierarchy)
        {
            Console.WriteLine(parent.Name);
        }
    }
}