DataReader调用

            

调用方法：

using (IDataReader dr = DbHelper.ExecuteReader(strSql))
            {
                while (dr.Read())
                {
                   //    赋值           

                }
                dr.Close();
            }

公共方法：

        public static IDataReader ExecuteReader(string strSql)
        {
            SqlConnection con = new SqlConnection(connectionString);
            SqlCommand command = new SqlCommand(strSql, con);
            con.Open();
            SqlDataReader reader = command.ExecuteReader();
            return reader;
        }