Пример отправки почты с использованием Unity

class Program
{
    static void Main(string[] args)
    {
        SmtpClient mailClient = new SmtpClient("smtp.qq.com");
        mailClient.EnableSsl = true;
        //Credentials для аутентификации при подключении к SMTP-серверу
        mailClient.Credentials = new NetworkCredential("1213250243@qq.com", "");
        //test@qq.com - адрес отправителя, test@tom.com - адрес получателя
        MailMessage message = new MailMessage(new MailAddress("1213250243@qq.com"), new MailAddress("aladdingame@qq.com"));
        // message.Bcc.Add(new MailAddress("tst@qq.com")); //можно добавить несколько получателей
        message.Body = "Hello Word! "; //текст сообщения
        message.Subject = "this is a test"; //тема сообщения
        //Attachment - вложение
        Attachment att = new Attachment(@"D:/test.mp3");
        message.Attachments.Add(att); //добавление вложения
        Console.WriteLine("Start Send Mail...");
        //Отправка...
        mailClient.Send(message);
        Console.WriteLine("Send Mail Successed");
        Console.ReadLine();
    }
}

using UnityEngine;
using System.Collections;
using System;
using System.Net;
using System.Net.Mail;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
``````csharp
public class SendEmailSrc : MonoBehaviour
{
    void OnGUI()
    {
        if (GUI.Button(new Rect(0, 50, 100, 40), "Capture"))
        {
            Debug.Log("Capture Screenshot");
            Application.CaptureScreenshot("screen.png");
        }
        if (GUI.Button(new Rect(0, 0, 100, 40), "Send"))
        {
            SendEmail();
        }
    }

    private void SendEmail()
    {
        MailMessage mail = new MailMessage();
        mail.From = new MailAddress("1213250243@qq.com");
        mail.To.Add("1213250243@qq.com");
        mail.Subject = "Test Mail";
        mail.Body = "This is for testing SMTP mail from GMAIL";
        mail.Attachments.Add(new Attachment("screen.png"));
        SmtpClient smtpServer = new SmtpClient("smtp.qq.com");
        smtpServer.Credentials = new System.Net.NetworkCredential("1213250243@qq.com", "пароль") as ICredentialsByHost;
        smtpServer.EnableSsl = true;
        ServicePointManager.ServerCertificateValidationCallback =
            delegate(object s, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
            { return true; };
        smtpServer.Send(mail);
        Debug.Log("успех");
    }
}

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