login page

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.Data;

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(@"Data Source=CODEM-PC;Initial Catalog=technology;Integrated Security=True;Connect Timeout=15;Encrypt=False;TrustServerCertificate=False");
        SqlCommand cmd = new SqlCommand("select * from anvesh where username=@u and password=@p", con);
        cmd.Parameters.AddWithValue("@u", TextBox1.Text);
        cmd.Parameters.AddWithValue("@p", TextBox2.Text);
        SqlDataAdapter sda = new SqlDataAdapter(cmd);
        DataTable dt = new DataTable();
        sda.Fill(dt);
        if (dt.Rows.Count > 0)
        {
            Response.Redirect("retrive.aspx");
        }
        else
        {
            ClientScript.RegisterStartupScript(Page.GetType(), "validation", "<script language='javascript'>alert('Invalid Username and Password')</script>");
        }

    }
}