C# 用树视图数据填充组合框

我问了一个关于将树视图数据放入组合框的问题

    public MainForm()
    {
        InitializeComponent();

            var list = TVProperties.Nodes
                   .Cast<TreeNode>()
                   .Select(x => x.Text)
                   .ToList();

        CmboExpenseType.DataSource = list;

        var Clist = TVProperties.Nodes[0].Nodes
       .Cast<TreeNode>()
       .Select(x => x.Text)
       .ToList();

        CmboExpenseDetail.DataSource = Clist;

    }

---

这是我的树视图和一些子节点。我想知道我是否在代码方面做了一些错误的事情，您是否可以给我任何帮助。

您需要将重点放在treeview上：

private void CmboExpenseType_SelectedIndexChanged(object sender, EventArgs e)
{
    var node = CmboExpenseType.SelectedItem as TreeNode;
    if(node == null)
        return;

    TVProperties.Focus();
    TVProperties.SelectedNode = node; 
}

private void CmboExpenseType_SelectedIndexChanged(object sender, EventArgs e)
{
    var node = CmboExpenseType.SelectedItem as TreeNode;
    if(node == null)
        return;

    TVProperties.Focus();
    TVProperties.SelectedNode = node; 
}