asp .Net TreeView实现数据绑定和事件响应

最近做了一个图书馆管理系统，其中要实现中图法分类号查询，因为初学asp ，感觉还有点难度，

第一步：数据库文件

第二步 向界面中拖进TreeView控件

第三步添加事件

下面是cs文件代码

 //TreeView绑定数据库
    public void BindDataBase(string sql){
        string str = System.Configuration.ConfigurationManager.
              ConnectionStrings["conn"].ToString();
        SqlConnection connection = new SqlConnection(str);
        try
        {
            connection.Open();
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }

        SqlCommand sqlCmd = new SqlCommand(sql, connection);

        SqlDataAdapter custDA = new SqlDataAdapter();
        custDA.SelectCommand = sqlCmd;
        DataSet ds = new DataSet();
        custDA.Fill(ds, "BookType");

        TreeNode root = new TreeNode("中图法分类");//新建根节点
        this.Kind_Tree.Nodes.Add(root);
        for (int i = ; i < ds.Tables["BookType"].Rows.Count; i++)
        {
            string parent=ds.Tables["BookType"].Rows[i][].ToString();//获取数据库中标记节点
            if(parent=="root"){//判断是否是根节点下的子节点
                TreeNode tree2 = new TreeNode(ds.Tables["BookType"].Rows[i][].ToString()
                    + ds.Tables["BookType"].Rows[i][].ToString());//创建一级子节点
            root.ChildNodes.Add(tree2);
           /*for (int j = 0; j < ds.Tables["BookType"].Rows.Count; j++)
            {
                string myparent = ds.Tables["BookType"].Rows[i][2].ToString();
                if (myparent == tree2.Text.ToString())
                {
                    TreeNode tree3 = new TreeNode(ds.Tables["BookType"].Rows[i][0].ToString() + ds.Tables["BookType"].Rows[i][1].ToString());
                    tree2.ChildNodes.Add(tree3);
                }
            }*/
            }
        }
        for (int j = ; j < root.ChildNodes.Count; j++)
        {
            TreeNode rootChild = root.ChildNodes[j];//获取根节点下的子节点
            for (int k = ; k < ds.Tables["BookType"].Rows.Count; k++)
            {
                string parent = ds.Tables["BookType"].Rows[k][].ToString();//获取数据库中标记节点

                if (parent == rootChild.Text.ToString().Substring(,))//判断是否是二级子节点
                {
                    TreeNode tree3 = new TreeNode(ds.Tables["BookType"].Rows[k][].ToString()
                        +"-"+ ds.Tables["BookType"].Rows[k][].ToString());//新建二级子节点
                    rootChild.ChildNodes.Add(tree3);
                }
            }
        }

        //TreeNode rootChil = root.ChildNodes[0];
       // Response.Write(rootChil.Text.ToString().Substring(0,1));
            connection.Close();
    }

    //TreeView的响应事件

    protected void Kind_Tree_SelectedNodeChanged(object sender, EventArgs e)
    {
        string s = Kind_Tree.SelectedNode.ValuePath.ToString();
        char[] spitChar = new char[] { '/' };
        string[] nodeValues = s.Split(spitChar);
        string sql = null;
        if (nodeValues.Length == )
        {
            string typeId = nodeValues[].Substring(, );
             sql = "select 图书编号,出版社,作者,书名,图书ISBN号,分类 from bookTable d, BookType t where t.BoType_id like '"
                + typeId + "%' and t.BoType_name=d.分类";
        }
        else {
             char[] spitChar2 = new char[] { '-' };
             string[] typeId2 = nodeValues[].Split(spitChar2);
              sql = "select 图书编号,出版社,作者,书名,图书ISBN号,分类 from bookTable d, BookType t where t.BoType_id ='"
                 + typeId2[] + "' and t.BoType_name=d.分类";
        }

        SqlDataSource1.SelectCommand = sql;
        Response.Write(nodeValues.Length);
    }

protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack) {

                string sql = "select * from BookType";
                BindDataBase(sql);
                Kind_Tree.ShowLines = true;
                Kind_Tree.ExpandDepth = ;

       }
}

显示时，因为节点的文本太长，如果要设置自动换行，还需要设置TreeView的属性

NodeWrap = true