using System;using System.Collections.Generic;using System.Linq;using System.Net.Mail;using System.Text;using System.Threading.Tasks;namespace QQEmail{    class Program    {        static void Main(string[] args)        {            for (int i = 0; i < 50; i++)            {                MailMessage mymail = new MailMessage();                mymail.From = new System.Net.Mail.MailAddress("邮箱@qq.com");                mymail.To.Add("haoliu2050@163.com");                mymail.Subject = "C#自动发送邮件测试 From HaoLiu TO 1399449842@qq.com";                mymail.Body = "不好意思，我在测试程序，刚才把QQ号写错了，Sorry！";                mymail.IsBodyHtml = true;                SmtpClient smtpclient = new SmtpClient();                smtpclient.DeliveryMethod = SmtpDeliveryMethod.Network;                smtpclient.Host = "smtp.qq.com";                smtpclient.Credentials = new System.Net.NetworkCredential("邮箱@qq.com", "密码");                try                {                    smtpclient.Send(mymail);                    Console.WriteLine("发送成功");                }                catch (Exception ex)                {                    Console.WriteLine("发送邮件失败.请检查是否为qq邮箱，并且没有被防护软件拦截");                }            }        }    }}