protected void Button1_Click(object sender, EventArgs e)
    {
        Session["username"] = txtusername.Text;
        Session["password"] = pass.Text;
        string pwd = con1.emplog(txtusername.Text);

        if (pwd == "user")
        {
            Response.Redirect("user.aspx");
        }
        else
        if (pwd == "admin" || pwd == "Admin")
        {
            Response.Redirect("admin.aspx");
        }
        else
        {
            MessageBox.Show("Invalid User or Password");
        }
    }