用asp.net写的一段代码,原理好像挺简单的,可运行结果就是出不来,但也没有任何错误提示,请高手帮我看看,问题出在哪:
SqlConnection con = new SqlConnection(strcon );
            con.Open();
 string sql = "select * from ComeTable";
                SqlDataAdapter da = new SqlDataAdapter(sql,con);
                DataSet ds = new DataSet();
                da.Fill(ds,"ComeTable");
                DataTable  dt=ds.Tables["ComeTable"];
                SqlCommand cmd = new SqlCommand(sql , con);
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.Read())
                {
                    DataView dv = new DataView(dt);
                    total.Text = "共" + dv.Count + "行";
                    dataGrid1.DataSource = dv;
                }