protected void btnLogin_Click(object sender, EventArgs e) { if (Session["users"] != null) { Session.Contents.Remove("users"); } Connect(txttendn.Text, txtmatkhau.Text); if (login == true) { if (Session["nextpage"] != null) { NextPage nextPage = (NextPage)Session["nextpage"]; Response.Redirect(nextPage.getNextWeb()); } Session.Add("userName", txttendn.Text); Session.Add("userPass", txtmatkhau.Text); Response.Redirect("Trangchu.aspx"); } else { lblthongbao.Text = "Check your password and username again"; } }