一、控制台程序

using System;
using System.Net;
using System.Net.Mail;public class EmailSender
{public void SendEmail(string toAddress, string subject, string body){// 设置发件人邮箱地址以及授权码string fromAddress = "xxxxx@qq.com";string password = "wxxxxxdgtdzhecjb";// 创建邮件消息对象MailMessage mail = new MailMessage();mail.From = new MailAddress(fromAddress);mail.To.Add(new MailAddress(toAddress));mail.Subject = subject;mail.Body = body;// 创建SMTP客户端对象，设置SMTP服务器和端口号(这里不用改)SmtpClient smtpClient = new SmtpClient("smtp.qq.com", 587);smtpClient.UseDefaultCredentials = false;smtpClient.Credentials = new NetworkCredential(fromAddress, password);smtpClient.EnableSsl = true;try{// 发送邮件smtpClient.Send(mail);Console.WriteLine("邮件发送成功！");}catch (Exception ex){Console.WriteLine("发送邮件时出现错误： " + ex.Message);}}
}
public class Test
{static int Main(string[] args){EmailSender emailSender = new EmailSender();emailSender.SendEmail("yyyyyyy@qq.com", "测试邮件", "这是一封测试邮件");//发送地址、邮箱标题、邮箱内容return 0;}
}

二、注册授权码

申请授权码：

第一步，登录QQ邮箱，点击设置-账号-找到下图位置点击开启服务

第二步，按照步骤指引，发送短信

第三步，记住授权码（后续无法查看授权码，但是可以生成多个授权码，不该邮箱密码不会过期）