using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace MeuProjeto.LocalClasse
{
    public class GmailEmailService
    {

    }
}

namespace MeuProjeto.LocalClasse
{

}

public interface IEmailService
{
    bool SendEmailMessage(EmailMessage message);
}
public class SmtpConfiguration
{
    public string Username { get; set; }
    public string Password { get; set; }
    public string Host { get; set; }
    public int Port { get; set; }
    public bool Ssl { get; set; }
}
public class EmailMessage
{
    public string ToEmail { get; set; }
    public string Subject { get; set; }
    public string Body { get; set; }
    public bool IsHtml { get; set; }
}
public class GmailEmailService : IEmailService
{
    private readonly SmtpConfiguration _config;
    public GmailEmailService()
    {
        _config = new SmtpConfiguration();
        var gmailUserName = "seue-mail@gmail.com";
        var gmailPassword = "suasenha";
        var gmailHost = "smtp.gmail.com";
        var gmailPort = 587;
        var gmailSsl = true;
        _config.Username = gmailUserName;
        _config.Password = gmailPassword;
        _config.Host = gmailHost;
        _config.Port = gmailPort;
        _config.Ssl = gmailSsl;
    }
    public bool SendEmailMessage(EmailMessage message)
    {
        var success = false;
        try
        {
            var smtp = new SmtpClient
            {
                Host = _config.Host,
                Port = _config.Port,
                EnableSsl = _config.Ssl,
                DeliveryMethod = SmtpDeliveryMethod.Network,
                UseDefaultCredentials = false,
                Credentials = new NetworkCredential(_config.Username, _config.Password)
            };
            using (var smtpMessage = new MailMessage(_config.Username, message.ToEmail))
            {
                smtpMessage.Subject = message.Subject;
                smtpMessage.Body = message.Body;
                smtpMessage.IsBodyHtml = message.IsHtml;
                smtp.Send(smtpMessage);
            }
            success = true;
        }
        catch (Exception ex)
        {
            //todo: add logging integration
            //throw;
        }
        return success;
    }
}

var gmailUserName = "seue-mail@gmail.com";
 var gmailPassword = "suasenha";

GmailEmailService gmail = new GmailEmailService();
    EmailMessage msg = new EmailMessage();
    msg.Body = mensagem;
    msg.IsHtml = true;
    msg.Subject = "Cadastro Realizado";
    msg.ToEmail = "destinatario@email.com";
    gmail.SendEmailMessage(msg);

using (SmtpClient client = new SmtpClient("smtp.gmail.com", 587)
    {
        Credentials = new NetworkCredential("meumail@gmail.com", "password"),
        EnableSsl = true
    })
{
    client.Send("meumail@gmail.com", "seumail@gmail.com", "test", "test");
}