请教 问题 —— 个人信息修改 修改不了
 protected void ImageButton1_Click(object sender, ImageClickEventArgs e)
    {

     
        string id = TextBox1.Text;  
        string cellphone = TextBox5.Text;
        string name = TextBox6.Text;
        string socialNum = TextBox7.Text;
        string email = TextBox8.Text;
        string sex = DropDownList1.SelectedValue.ToString();
        string zipcode = TextBox9.Text;
        string address = TextBox10.Text;

        string SQL = "UPDATE users SET  u_name='" + name + "',u_cellphone='" + cellphone + "',";
        SQL += "u_socialNum='" + socialNum + "',u_email='" + email + "',u_sex='" + sex + "',u_zipcode='" + zipcode + "',u_address='" + address + "' WHERE u_id='" + id + "';";


        SqlConnection conn = new SqlConnection(connectionString);
        SqlCommand cmd = new SqlCommand(SQL, conn);

        conn = new SqlConnection(connectionString);
        cmd = new SqlCommand(SQL, conn);
        SqlDataReader rd;
         
        try
        {
            conn.Open();
            rd = cmd.ExecuteReader();
            rd.Read();
            Response.Write("<script>alert('?? ???????!!!');</script>");
            rd.Close();
           
        }
        catch (Exception error)
        {
             Response.Write("<script>alert('?? ???????!!!');</script>");
        }
        finally
        {
            conn.Close();
        }



点解修改按钮时 页面就变成个空白页面 这个修改函数部分哪里错了呢  谢谢 帮帮看下