随机查询

 DataTable dt = SystemBLL.DataSeachBLL.GetFillUnitNames();
            DataRow dr = dt.NewRow();
            dt.Rows.Add(SystemBLL.DataSeachBLL.GetUnitnamesss().Rows[0][0].ToString());
            int count = dt.Rows.Count;
            Random ran = new Random();
            if (count > 0)
            {
                int RandKey = ran.Next(0, count);
                string strsql = dt.Rows[RandKey][0].ToString();
                selectcity.Text = "本次随机查询的地区是：" + strsql+"的统计情况";
                GVStatistics.DataSource = SystemBLL.DataSeachBLL.SystematicRandomStatisticals(DateTime.Now.Year.ToString(),strsql);
            }
            else
            {
                MessageBox.Show("数据库暂时无任何部门信息！");
            }