private void btnCheckEmail_Click(object sender, EventArgs e) { if (ManageSystem.CheckForInternetConnection()) { int idUser = ManageSystem.SearchEmail(txtCheckEmail.Text); if (idUser == -1) { MessageBox.Show("Email không tồn tại!", "Message", MessageBoxButtons.OK, MessageBoxIcon.Warning); } else { txtPassForget.Visible = true; txtRePassForget.Visible = true; txtValidateCode.Visible = true; lblBack.Visible = true; btnConfirm.Visible = true; txtCheckEmail.Visible = false; btnCheckEmail.Visible = false; this.AcceptButton = this.btnConfirm; ClearTextBox(); string code = GenerateCode(); string tk = "vocabularyup1903"; string mk = "123456789vn"; string port = "587"; string SMTP = "smtp.gmail.com"; string Messge = "Mã xác nhận của bạn là : " + code; string To = txtCheckEmail.Text; string cc = ""; string subject = "Your Code"; login = new NetworkCredential(tk, mk); client = new SmtpClient(SMTP); client.Port = Convert.ToInt32(port); client.EnableSsl = checkBox.Checked; client.Credentials = login; msg = new MailMessage { From = new MailAddress(tk + SMTP.Replace("smtp.", "@"), "Trung tâm Vocabulary-Up", Encoding.UTF8) }; msg.To.Add(new MailAddress(To)); if (!string.IsNullOrEmpty(cc)) { msg.To.Add(new MailAddress(cc)); } msg.Subject = subject; msg.Body = Messge; msg.BodyEncoding = Encoding.UTF8; msg.IsBodyHtml = true; msg.Priority = MailPriority.Normal; msg.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure; client.SendCompleted += new SendCompletedEventHandler(SendOrPostCallback); string userstate = "Sending..."; client.SendAsync(msg, userstate); verifiedCode = code; countDown.Start(); countDownText.Start(); btnCheckEmail.Enabled = false; } } else { MessageBox.Show("Kết nối có vấn đề!"); } }