c# - 如何使用Asp.net在树 View 中动态添加根节点

我想将DataTable绑定到TreeView。我编写了以下代码。它当前正在工作，意味着它显示DataTable的所有数据，但没有根节点。

 List<DocumentData> lstData = GetSPDocuments();
    gvDocuments.DataSource = lstData;
    gvDocuments.DataBind();

    DataTable dt = ConvertToDataTable(lstData);

    TreeNode node1 = new TreeNode("Root");


    foreach (DataRow r in dt.Rows)
    {
        int nodeLvl = int.Parse(r["ID"].ToString());
        string nodeParent = "Folders";
        string nodeName = r["Title"].ToString();


        TreeNode tNode = new TreeNode(nodeName);

        ht.Add(nodeLvl.ToString() + nodeName, tNode);

        if (tvDocs.Nodes.Count == 0)
            tvDocs.Nodes.Add(tNode);
        else
        {
            nodeLvl--;
            tvDocs.Nodes.Add(tNode);
        }
    }

如何在此处添加静态根节点？？？请帮忙！

最佳答案

试试这个可能会有所帮助。

 protected void Page_Load(object sender, EventArgs e)
    {
        conStr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
        conn = new OleDbConnection(conStr);
        BindTreeViewControl();
    }

    private void BindTreeViewControl()
    {
        try
        {
            DataSet ds = GetDataSet("Select ProductId,ProductName,ParentId from ProductTable");
            DataRow[] Rows = ds.Tables[0].Select("ParentId = 0");

            for (int i = 0; i < Rows.Length; i++)
            {
                TreeNode root = new TreeNode(Rows[i]["ProductName"].ToString(), Rows[i]["ProductId"].ToString());
                root.SelectAction = TreeNodeSelectAction.Expand;
                CreateNode(root, ds.Tables[0]);
                treeviwExample.Nodes.Add(root);
            }
        }
        catch (Exception Ex) { throw Ex; }
    }

    public void CreateNode(TreeNode node, DataTable Dt)
    {
        DataRow[] Rows = Dt.Select("ParentId =" + node.Value);
        if (Rows.Length == 0) { return; }
        for (int i = 0; i < Rows.Length; i++)
        {
            TreeNode Childnode = new TreeNode(Rows[i]["ProductName"].ToString(), Rows[i]["ProductId"].ToString());
            Childnode.SelectAction = TreeNodeSelectAction.Expand;
            node.ChildNodes.Add(Childnode);
            CreateNode(Childnode, Dt);
        }
    }
    private DataSet GetDataSet(string Query)
    {
        DataSet Ds = new DataSet();
        try
        {
            OleDbDataAdapter da = new OleDbDataAdapter(Query, conn);
            da.Fill(Ds);
        }
        catch (Exception dex) { }
        return Ds;
    }

和数据库结构是