解决方法如下：
SqlCommand sold_cmd = new SqlCommand(sql_sold,conn);
sold_cmd.CommandTimeout = 300;
SqlCommand detail_cmd = new SqlCommand(sql_detail,conn);
detail_cmd.CommandTimeout = 300;
sqlDA_sold.SelectCommand = sold_cmd;
sqlDA_detail.SelectCommand = detail_cmd;
责任编辑：小草
