模仿树形控件显示效果

建立树形结构：

#region
        protected StringBuilder CreateTreeView()
        {
            string sql = "类型表";
            StringBuilder sb = new StringBuilder();
            OperateData ort = new OperateData();
            DataTable dt = ort.ExcuteToDataSet(sql).Tables["mytable"];
            sb.Append("|_<a href=NewsType.aspx?id=0>根目录</a><br>");
            CreateTreeViewRecursive(sb, dt, 0);
            dt.Dispose();
            ort = null;
            return sb;
        }
       
        /// <summary>
        /// 递归查询
        /// </summary>
        /// <param name="nodes">TreeView的节点集合</param>
        /// <param name="dataSource">数据源</param>
        /// <param name="parentid">上一级行政区划的标识码</param>
        protected void CreateTreeViewRecursive(StringBuilder mysb, DataTable dataSource, int parentid)
        {
            string filter;
            filter = string.Format("p_oid={0}", parentid);
            DataRow[] drarr = dataSource.Select(filter);
            foreach (DataRow dr in drarr)
            {
                if (parentid == 0)
                {
                    mysb.Append("|&nbsp;&nbsp;&nbsp;&nbsp;|_<a href=NewsType.aspx?id=" + dr["p_id"].ToString() + "><font color=red>" + (string)dr["p_type"] + "</font></a><br>");
                }
                else if (getMain(parentid.ToString()) == "0")
                {
                    mysb.Append("|&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;|_<a href=NewsType.aspx?id=" + dr["p_id"].ToString() + ">" + (string)dr["p_type"] + "</a><br>");
                }
                else
                {
                    mysb.Append("|&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;|_<a href=NewsType.aspx?id=" + dr["p_id"].ToString() + ">" + (string)dr["p_type"] + "</a><br>");
                }
                CreateTreeViewRecursive(mysb, dataSource, Int32.Parse(dr["p_id"].ToString()));
            }
        }
        #endregion

前台调用可以用label显示输出的结果。

效果截图：