How to search Hierarchical Data with Linq

Question

I need to search a tree for data that could be anywhere in the tree. How can this be done with linq?

class Program
{
    static void Main(string[] args) {

         


        

Answer 1

I have tried two of the suggested codes and made the code a bit more clear:

    public static IEnumerable Flatten1(this T source, Func> selector)
    {
        return selector(source).SelectMany(c => Flatten1(c, selector)).Concat(new[] { source });
    }

    public static IEnumerable Flatten2(this T source, Func> selector)
    {            
        var stack = new Stack();
        stack.Push(source);
        while (stack.Count > 0)
        {
            var current = stack.Pop();
            yield return current;
            foreach (var child in selector(current))
                stack.Push(child);
        }
    }

Flatten2() seems to be a little bit faster but its a close run.