Send email using Gmail SMTP Mail Server in ASP.Net

private void Send()
    {
        try
        {
            string Subject = "This is test mail using smtp settings",
            Body = "sad",
            ToEmail = txtEmail.Text.Trim();

            string SMTPUser = "eDMS.tanphu@gmail.com", SMTPPassword = "myPass";

            //Now instantiate a new instance of MailMessage
            MailMessage mail = new MailMessage();

            //set the sender address of the mail message
            mail.From = new MailAddress(SMTPUser, "iDOC");

            //set the recepient addresses of the mail message
            mail.To.Add(ToEmail);

            //set the subject of the mail message
            mail.Subject = Subject;

            //set the body of the mail message
            mail.Body = Body;

            //leave as it is even if you are not sending HTML message
            mail.IsBodyHtml = true;

            //set the priority of the mail message to normal
            mail.Priority = MailPriority.Normal;

            //instantiate a new instance of SmtpClient
            SmtpClient smtp = new SmtpClient();

            //if you are using your smtp server, then change your host like "smtp.yourdomain.com"
            smtp.Host = "smtp.gmail.com";

            //chnage your port for your host
            smtp.Port = 25; //or you can also use port# 587

            //provide smtp credentials to authenticate to your account
            smtp.Credentials = new System.Net.NetworkCredential(SMTPUser, SMTPPassword);
            smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
            //if you are using secure authentication using SSL/TLS then "true" else "false"
            smtp.EnableSsl = true;

            smtp.Send(mail);
        }
        catch (SmtpException ex)
        {
        }
    }