TreeView控件

public partial class WebForm1 : System.Web.UI.Page
{
        DataSet dsTreeView = new DataSet();

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                GetTreeView();
                InitTree("", null);
                TreeView1.ExpandDepth = ;//展开目录
                TreeView1.Nodes[].Expanded = true;//默认只展开第2层目录
            }
        }

        private void InitTree(string parent_code, TreeNode parent_node)
        {
            DataView dv = dsTreeView.Tables[].DefaultView;
            dv.RowFilter = "[parent_code] = '" + parent_code + "'";

            foreach (DataRowView Row in dv)
            {
                TreeNode node = new TreeNode();
                node.SelectAction = TreeNodeSelectAction.Expand;
                if (parent_node == null)//根节点
                {
                    node.Text = Row["area_name"].ToString();
                    node.Value = Row["area_code"].ToString();
                    this.TreeView1.Nodes.Add(node);
                    InitTree(Row["area_code"].ToString(), node);//递归
                }
                else
                {
                    node.Text = "<div onclick=\"javascript:SetView('" + Row["area_name"].ToString() + "')\">" + Row["area_name"].ToString() + "</div>";//绑定前台JS事件
                    node.Value = Row["area_code"].ToString();
                    parent_node.ChildNodes.Add(node);
                    InitTree(Row["area_code"].ToString(), node);//递归
                }
            }
        }

        /// <summary>
        /// 数据源
        /// </summary>
        private void GetTreeView()
        {
            SqlConnection sqlConn = new SqlConnection("server=.;database=test;uid=test;pwd=test");
            SqlDataAdapter adp = new SqlDataAdapter("select area_code,area_name,parent_code from tbl_all_AreaList where area_code<>parent_code", sqlConn);
            adp.Fill(dsTreeView);
        }

    }