protected void submit_Click(object sender, EventArgs e)
    {
        con.connect();
        Session["ID"] = uname.Text;
        string str = con.login(uname.Text, password.Text);

        if (password.Text == str)
        {
            string str1 = con.logrole(uname.Text);
            if (str1 == "Student")
            {
                Response.Redirect("student.aspx");
            }
            else if (str1 == "Staff")
            {
                Response.Redirect("staff.aspx");
            }
            else if (str1 == "Accountant")
            {
                Response.Redirect("accountant.aspx");
            }
            else if (str1 == "Admin")
            {
                Response.Redirect("admin.aspx");
            }
        }
    }