.NET CORE 下收发邮件之 MAILKIT

背景

利用代码发送邮件在工作中还是比较常见的，相信大家都用过SmtpClient来处理发送邮件的操作，不过这个类以及被标记已过时，所以介绍一个微软推荐的库MailKit来处理。

MailKit开源地址：https://github.com/jstedfast/MailKit.

需要邮件功能

1、服务提供方:需提供邮件收发客户端或Web服务。如:QQ邮箱、GMail邮箱、126、163等知名邮件服务提供商。注:如果你使用的第三方不知名邮件服务商提供的邮件收发服务,通过其发出的邮件,可能会被其他知名邮件服务提供商的STMP服务器视为是"恶意邮件或垃圾邮件"!

2、消息推送:消息推送方

3、App:某些网站会员的注册功能或者功能激活功能。

协议

1、SMTP(Simple Mail Transfer Protocol)   ---简单邮件传输协议

2、POP3(Post Office Protocol -Version3)   ---邮局协议第三个版本

代码实现

1、新建项目 引用 MailKit

using MailKit.Net.Smtp;using MimeKit;

2、指定发件人、收件人、附件等信息

    [HttpPost]
        [Route("sendmail")]
        public bool Sendmail(SendmailDto model)
        {
            string mailTo = model.mail;
            string title = model.title;
            string requestId = Guid.NewGuid().ToString("N");
            string path = WriteFilepath(requestId, title + ".html", model.str);
            string docpath = path.Replace(".html", ".docx");
            try
            {
                string applicationRoot = AppContext.BaseDirectory;
                var provider = new PhysicalFileProvider(applicationRoot);

                string apath = @"C:/www/fengnan";
                // string apath = @"C:/net6.0";

                var filePath =
                 //applicationRoot +
                 apath + $"/Template/fldoc/" + requestId + "/";
                var filePath2 =
               //applicationRoot +
               apath + $"/Template/fldoc/" + requestId + "/"
                  + title + ".html";

                ecmd("soffice --headless --convert-to docx:\"Office Open XML Text\" " + filePath2 + " --outdir " + filePath);

                //   string docpath = path.Replace(".html", ".docx");
            }
            catch (Exception ex)
            {
                _logger.Error(ex);
            }

            // string mailFrom = "xxxx@qq.com";
            string mailFrom = "xxx@xx.net";

            //   mailTo = "xx@xxx.com";
            string Text = "内容见附件，请查收<br/> 感谢";
            ////string mailFromAccount = "xxx@qq.com";
            ////string mailPassword = "xxxx";

            string mailFromAccount = "xxx@xx.net";
            string mailPassword = "xxxx@";

            var contentRoot = Directory.GetCurrentDirectory();
            var webRoot = Path.Combine(contentRoot, "wwwroot");
            ///  string path = Path.Combine(webRoot, "Images/icc.png");

            //  string path = @"D:\xxxx知.html";

            //  string Text = @"Hey Chandler,

            //I just wanted to let you know that Monica and I were going to go play some paintball, you in?

            //-- Joey";

            Config eConfig = new Config
            {                From = new MailAddress("xxxx", mailFrom),
                //  Host = "smtp.qq.com",                Host = "smtp.exmail.qq.com",                MailFromAccount = mailFromAccount,                MailPassword = mailPassword,
                // Port = 587,                Port = 465,                UseSsl = true,                IsHtml = true
            };

            List<MailAddress> tos = new List<MailAddress>();
            tos.Add(new MailAddress("", mailTo));

            List<string> flist = new List<string>();

            if (System.IO.File.Exists(docpath))
            {
                flist.Add(docpath);
                //docpath
            }
            else
            {
                flist.Add(path);
            }

            Mailhelper.SendEmail(eConfig, tos, title, Text, flist.ToArray());

            return true;
        }

3、发邮件帮助类

using MimeKit;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Threading.Tasks;
namespace DFTech.Service.Filters
{
    /// <summary>
    /// 发邮件
    /// </summary>
    public class Mailhelper
    {
        /// <summary>
        /// 发邮件
        /// </summary>
        /// <param name="config"></param>
        /// <param name="tos"></param>
        /// <param name="subject"></param>
        /// <param name="message"></param>
        /// <param name="attachments"></param>
        /// <returns></returns>
        public  static void SendEmail(Config config, List<MailAddress> tos, string subject, string message, params string[] attachments)
        {
            var emailMessage = new MimeMessage();

            emailMessage.From.Add((MailboxAddress)config.From);
            foreach (var to in tos)
                emailMessage.To.Add(to as MailAddress);

            emailMessage.Subject = subject;

            var alternative = new Multipart("alternative");
            if (config.IsHtml)
                alternative.Add(new TextPart("html") { Text = message });
            else
                alternative.Add(new TextPart("plain") { Text = message });

            if (attachments != null)
            {
                foreach (string f in attachments)
                {
                    var attachment = new MimePart()//("image", "png")
                    {
                        ContentObject = new ContentObject(File.OpenRead(f), ContentEncoding.Default),
                        ContentDisposition = new ContentDisposition(ContentDisposition.Attachment),
                        ContentTransferEncoding = ContentEncoding.Base64,
                        FileName = Path.GetFileName(f)
                    };
                    alternative.Add(attachment);
                }
            }
            emailMessage.Body = alternative;

            using (var client = new SmtpClient())
            {
                 client.Connect(config.Host, config.Port, config.UseSsl);// SecureSocketOptions.None
                client.AuthenticationMechanisms.Remove("XOAUTH2");

                 client.Authenticate(config.MailFromAccount, config.MailPassword);
                 client.Send(emailMessage);
                 client.Disconnect(true);
            }
        }
    }

    public class Config
    {
        public int Port { get; set; } = 25; //25
        public string Host { get; set; } //smtp.hantianwei.cn

        public bool IsHtml { get; set; } = true;

        public bool UseSsl { get; set; } = false;

        public string MailFromAccount { get; set; }//mail@hantianwei.cn
        public string MailPassword { get; set; }

        public MailAddress From { get; set; }
    }

    /// <summary>
    ///
    /// </summary>
    public class MailAddress : MailboxAddress
    {
        public MailAddress(string name, string address) : base(name, address)
        {
        }

        public MailAddress(Encoding encoding, string name, string address) : base(encoding, name, address)
        {
        }
    }
}