public JsonResult Practice_example(long pqid) { var dbq = db.paper_ques.Find(pqid); var back = dbq.question.qbase_chapter.background; DataSet[] res = null; if (back.db == "Kingbase") { var kingbaseconn = new KingbaseConn(); res = kingbaseconn.ShowBackGround(back.name); kingbaseconn.Dispose(); } else if (back.db == "Mysql") { var mysqlconn = new MysqlConn(); res = mysqlconn.ShowBackGround(back.name); mysqlconn.Dispose(); } else if (back.db == "MSSQL") { var mssqlconn = new MSSQLConn(); res = mssqlconn.ShowBackGround(back.name); mssqlconn.Dispose(); } else { res = new DataSet[0]; } int count = res.Count(); var tname = new List <string>(); var datas = new List <object[]>(); string[][] colnames = new string[count][]; for (int i = 0; i < count; i++) { var ds = res[i]; var colcount = ds.Tables[0].Columns.Count; tname.Add(ds.DataSetName); colnames[i] = new string[colcount]; int j = 0; foreach (DataColumn col in ds.Tables[0].Columns) { colnames[i][j] = new string(col.ColumnName.ToCharArray()); //colnames[i][j] += $"({col.GetType().ToString()})"; j++; } var data = ds.Tables[0].Rows[0].ItemArray; datas.Add(data); } var json = new { count, tname, datas, colnames }; return(Json(json, JsonRequestBehavior.AllowGet)); }