traverse unity gameobject's hierarchy by recursion

unity-gameobject-traveller.cs

/*
 * https://en.wikipedia.org/wiki/Tree_(data_structure)
 */

private static List<GameObject> Traverse(GameObject parent, Type type)
{
    List<GameObject> children = new List<GameObject>();
    foreach (Transform node in parent.transform)
        children.Add(node.gameObject);

    // store target gameObjects
    List<GameObject> targets = new List<GameObject>();

    if (parent.GetComponent(type) != null)
        targets.Add(parent);

    foreach (GameObject child in children)
    {
        // pick out gameObject with the component
        if (child.GetComponent(type) != null)
            targets.Add(child);

        // if child is a internal node, repeat.
        if (child.transform.childCount > 0)
            foreach (GameObject inn in Traverse(child, type))
                if (!targets.Contains(inn))
                    targets.Add(inn);
    }

    return targets;
}