protected void Asignin_Click(object sender, EventArgs e)
    {
        DataTable dt = new DataTable();

        li.user_name      = adminUname.Text;
        li.admin_password = adminPassword.Text;
        dt = li.o_login(li);
        if (dt.Rows.Count > 0)
        {
            Session["Uplace_name"] = dt.Rows[0]["Uplace_name"].ToString();
            Response.Redirect("operator_home.aspx");
        }
        else
        {
            ClientScript.RegisterStartupScript(Page.GetType(), "validation", "<script language='javascript'>alert('Invalid Username and Password')</script>");
        }
    }