后台拼接tree的json格式

public static string GetChannelTreeNodeJson()
        {
            Database db = DatabaseFactory.CreateDatabase();
            string sql = @"SELECT PageId
                          ,pageName
                          ,cregex
                          ,parentId
                          ,dregex FROM LogFile_Page ";
            DbCommand mycmd = db.GetSqlStringCommand(sql);
            DataSet ds = db.ExecuteDataSet(mycmd);
            System.Text.StringBuilder s = new System.Text.StringBuilder();
            if (ds != null && ds.Tables.Count > 0)
            {
                DataTable dt = ds.Tables[0];
                s.Append(GetChildNodes(dt, "00"));
                s = s.Remove(s.Length - 2, 2);

            }
            return s.ToString();
        }
        public static string GetChildNodes(DataTable dt, string parentid)
        {
            StringBuilder stringbuilder = new StringBuilder();
            DataRow[] CRow = dt.Select("parentId=" + parentid);
            if (CRow.Length > 0)
            {
                stringbuilder.Append("[");
                for (int i = 0; i < CRow.Length; i++)
                {
                    string chidstring = GetChildNodes(dt, CRow[i]["PageId"].ToString());
                    if (!string.IsNullOrEmpty(chidstring))
                    {
                        stringbuilder.Append("{ \"id\":\"" + CRow[i]["PageId"].ToString() + "\",\"text\":\"" + CRow[i]["pageName"].ToString() + "\",\"state\":\"closed\",\"children\":");
                        stringbuilder.Append(chidstring);
                    }
                    else
                    {
                        stringbuilder.Append("{\"id\":\"" + CRow[i]["PageId"].ToString() + "\",\"text\":\"" + CRow[i]["pageName"].ToString() + "\"},");
                    }
                }
                stringbuilder.Replace(',', ' ', stringbuilder.Length - 1, 1);
                stringbuilder.Append("]},");
            }
            return stringbuilder.ToString();
        }