邮箱发送验证码

 public string sendingMail(string email)
        {
            string sendEmail = "157164@qq.com";//发件地址
            var SendVerificationCode = VerifyCode();//生成随机验证码


            //确定发件地址与收件地址
            MailAddress sendAddress = new MailAddress(sendEmail);//发件地址
            MailAddress receiveAddress = new MailAddress(email);//收件地址

            //构造一个Email的Message对象 内容信息
            MailMessage mailMessage = new MailMessage(sendAddress, receiveAddress);
            mailMessage.Subject = "测试主题";//邮件内容主题
            mailMessage.SubjectEncoding = Encoding.UTF8;//编码格式
            mailMessage.Body = $"验证码：{SendVerificationCode}（ 本邮件由系统自动发出，请勿回复 ）：";//邮件内容主题
            mailMessage.BodyEncoding = System.Text.Encoding.UTF8;//内容编码格式
            mailMessage.Priority = MailPriority.High;
            mailMessage.From = new MailAddress("157164@qq.com", "主题", Encoding.UTF8);
            mailMessage.To.Add(new MailAddress(email));

            System.Net.Mail.SmtpClient smtpClient = null;
            try
            {
                smtpClient = new System.Net.Mail.SmtpClient("stmp.qq.com")//符合邮箱的smtp协议
                {
                    Timeout = 20000,
                    Port = 587,
                    Credentials = new NetworkCredential("发件邮箱名称", "发件邮箱密码"),
                    EnableSsl = true
                };
                smtpClient.Send(mailMessage);
                _memoryCache.Set(email, new InsertUserMessageDto() { Code = SendVerificationCode, Email = email }, TimeSpan.FromMinutes(5));
            }
            catch (System.Net.Mail.SmtpException ex) { Console.WriteLine(ex.Message, "发送邮件出错"); }
            return "";
        }