public DataSet checkUser(string username, string pwd, string keys) { DataSet ds = new DataSet(); try { username = commons.RequestSafeString(username, 50); pwd = commons.RequestSafeString(pwd, 50); pwd = commons.GetMD5(pwd);//加密 string timenow = DateTime.Now.Year.ToString() + "-" + DateTime.Now.Month.ToString() + "-" + DateTime.Now.Day.ToString() + " 00:00:00"; string month = DateTime.Now.Month.ToString(); if (month.Length == 1) { month = "0" + month; } string days = DateTime.Now.Day.ToString(); if (days.Length == 1) { days = "0" + days; } string decryptTime = DateTime.Now.Year.ToString() + month + days; string keysnow = commons.Encrypt(timenow, decryptTime); //string keysnow = keys; if (keys == keysnow) { ds = usersBll.GetList("USERNAME='******' and PASSWORD='******' and DELFLAG=0"); } else { ds = null; } } catch { ds = null; } return(ds); }