ช่วยแก้โค้ดตรวจสอบการ log in ภาษา asp.net c# หน่อยค่ะ

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Configuration;

public partial class Login : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["RegConnectionString"].ConnectionString);
            con.Open();
            string cmdstr = "Select count(*) from Registration where UserName='" + TextBox1.Text + "'";
            SqlCommand checkuser = new SqlCommand(cmdstr, con);
            int temp = Convert.ToInt32(checkuser.ExecuteScalar().ToString());
            if (temp == 1)
            {
                string cmdstr2 = "Select Password from Registration where UserName='" + TextBox1.Text + "'";
                SqlCommand pass = new SqlCommand(cmdstr2, con);
                string password = pass.ExecuteScalar().ToString();
                con.Close();

                if (password == TextBox2.Text)
                {
                    Session["New"] = TextBox1.Text;
                    Response.Redirect("Secure.aspx");

                }
                else
                {
                    Label1.Visible = true;
                    Label1.Text = "Invalid Password...!!";
                }
            }
                 else
                {
                    Label1.Visible = true;
                    Label1.Text = "Invalid UserName...!!";
                }
            
            }
        }