class oraDataConnection
    {
        string serveraddress = "carmng";
        string userid = "carmng";

        public OracleConnection getcon(string server,string user)       //返回一个oracle连接
        {
            if (server == "")
                server = serveraddress;
            if (user == "")
                user = userid;

            string constr = "data source="+server+";user="+user+";password=cztesthp380";
            OracleConnection conora = new OracleConnection(constr);

            return conora;
        }

        public DataTable getdatatable(string server,string user,string cmdstr)     //返回一个指定查询的表
        {
            string constr = "data source=" + server + ";user=" + user + ";password=cztesthp380";
            OracleConnection oracon = new OracleConnection(constr);
            oracon.Open();
            DataTable dt = new DataTable();
            OracleDataAdapter ada = new OracleDataAdapter(cmdstr, oracon);
            ada.Fill(dt);
            oracon.Close();

            return dt;
        }

        public DataTable getdatatable(OracleConnection oracon, string cmdstr)     //返回一个指定查询的表
        {
            oracon.Open();
            DataTable dt = new DataTable();
            OracleDataAdapter ada = new OracleDataAdapter(cmdstr, oracon);
            ada.Fill(dt);
            oracon.Close();

            return dt;
        }

        public string insertitem(string server, string user, string cmdstr)        //增加操作
        {
            if (cmdstr.Substring(0, 12) != "insert into ")
            {
                return "非insert语句";
            }

            string constr = "data source=" + server + ";user=" + user + ";password=cztesthp380";
            OracleConnection oracon = new OracleConnection(constr);
            oracon.Open();
            OracleCommand cmd = new OracleCommand(cmdstr, oracon);
            cmd.ExecuteNonQuery();
            oracon.Close();

            return "1";
        }

        public string updateitem(string server, string user, string cmdstr)          //更新操作
        {
            if (cmdstr.Substring(0, 7) != "update ")
            {
                return "非update语句";
            }

            string constr = "data source=" + server + ";user=" + user + ";password=cztesthp380";
            OracleConnection oracon = new OracleConnection(constr);
            oracon.Open();
            OracleCommand cmd = new OracleCommand(cmdstr, oracon);
            cmd.ExecuteNonQuery();
            oracon.Close();

            return "1";
        }

        public string deleteitem(string server, string user, string cmdstr)            //删除操作
        {
            if (cmdstr.Substring(0, 12) != "delete from ")
            {
                return "非delete语句";
            }

            string constr = "data source=" + server + ";user=" + user + ";password=cztesthp380";
            OracleConnection oracon = new OracleConnection(constr);
            oracon.Open();
            OracleCommand cmd = new OracleCommand(cmdstr, oracon);
            cmd.ExecuteNonQuery();
            oracon.Close();

            return "1";
        }
    }