此函数仅查找树视图中的第一个节点,其中包含SearchText.
private TreeNode SearchNode(string SearchText,TreeNode StartNode)
{
    TreeNode node=null;
    while (StartNode!= null)
    {
        if (StartNode.Text.ToLower().Contains(SearchText.ToLower()))
        {
            node = StartNode; 
            break;
        };
        if (StartNode.Nodes.Count != 0) 
        {
            node=SearchNode(SearchText, StartNode.Nodes[0]);//Recursive Search
            if (node != null)
            {
                break;
            };
        };
        StartNode = StartNode.NextNode;
    };
    return node;
} 
private void button1_Click(object sender, EventArgs e)
{
    string SearchText = this.textBox1.Text;
    if (SearchText == "")
    {
        return;
    };
    TreeNode SelectedNode = SearchNode(SearchText, treeView1.Nodes[0]);
    if (SelectedNode != null)
    {
        this.treeView1.SelectedNode = SelectedNode;
        this.treeView1.SelectedNode.Expand();
        this.treeView1.Select();
    };
}
我应该如何更改它,以便该功能不仅可以找到第一个节点,而且可以找到所有节点,每次单击时button1,它都会找到下一个节点直到最后,然后从头开始?所以我不应该从 搜索TreeView1.Nodes[0],而是从TreeView1.SelectedNode...