使用Smtp协议发送邮件

发送代码，Mail类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Mail;
using System.Security.Cryptography.X509Certificates;
using System.Net.Security;namespace Smtp
{public class Mail{private string sender;/// <summary>/// 发送人/// </summary>public string Sender{get{return sender;}set{sender = value;}}private string senderMail;/// <summary>/// 发送人邮箱/// </summary>public string SenderMail{get{return senderMail;}set{senderMail = value;}}private string senderPw;/// <summary>/// 发送人密码/// </summary>public string SenderPw{get{return senderPw;}set{senderPw = value;}}private string smtpServer;/// <summary>/// smtpServer地址/// </summary>public string SmtpServer{get{return smtpServer;}set{smtpServer = value;}}/// <summary>/// /// </summary>/// <param name="sender">委托发件人</param>/// <param name="sender">委托发件人邮件地址</param>/// <param name="senderPw">密码</param>/// <param name="ewsUrl">smtpServer地址</param>public Mail(string sender, string senderMail, string senderPw, string smtpServer){this.sender = sender;this.senderMail = senderMail;this.senderPw = senderPw;this.smtpServer = smtpServer;}public Mail(){}/// <summary>/// 发送邮件/// </summary>/// <param name="title"></param>/// <param name="body"></param>/// <param name="receiver"></param>public void Send(string title, string body, string[] receiver){SmtpClient _smtpClient = new SmtpClient();_smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;//指定电子邮件发送方式_smtpClient.Host = this.smtpServer; ;//指定SMTP服务器_smtpClient.EnableSsl = true;_smtpClient.Port = 587;_smtpClient.Credentials = new System.Net.NetworkCredential(this.sender, this.senderPw);//用户名和密码for (int i = 0; i < receiver.Length; i++){//ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(ValidateServerCertificate);ServicePointManager.ServerCertificateValidationCallback =
delegate (Object obj, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors) { return true; };MailMessage _mailMessage = new MailMessage(this.senderMail, receiver[i]);_mailMessage.Subject = title;//主题_mailMessage.Body = body;//内容_mailMessage.BodyEncoding = System.Text.Encoding.UTF8;//正文编码_mailMessage.IsBodyHtml = true;//设置为HTML格式_mailMessage.Priority = MailPriority.High;//优先级//Attachment am = new Attachment(attachment, "attachment");//_mailMessage.Attachments.Add(am);_smtpClient.Send(_mailMessage);}}public static bool ValidateServerCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors){//if (sslPolicyErrors == SslPolicyErrors.None)//    return true;//else//    return true;// If there are no errors, then everything went smoothly.if (sslPolicyErrors == SslPolicyErrors.None)return true;// Note: MailKit will always pass the host name string as the `sender` argument.//var host = (string)sender;string host = sender as string;if (host == null){// Handle the case where sender is not a stringConsole.WriteLine("Sender parameter is not a valid string.");return false;}if ((sslPolicyErrors & SslPolicyErrors.RemoteCertificateChainErrors) != 0){// This means that there are errors in the certificate chain. You can inspect the chain errors and handle them accordingly.foreach (X509ChainStatus chainStatus in chain.ChainStatus){Console.WriteLine("Certificate chain error: " + chainStatus.StatusInformation);}return false;}if ((sslPolicyErrors & SslPolicyErrors.RemoteCertificateNotAvailable) != 0){// This means that the remote certificate is unavailable. Notify the user and return false.Console.WriteLine("The SSL certificate was not available for {0}", host);return false;}if ((sslPolicyErrors & SslPolicyErrors.RemoteCertificateNameMismatch) != 0){// This means that the server's SSL certificate did not match the host name that we are trying to connect to.var certificate2 = certificate as X509Certificate2;var cn = certificate2 != null ? certificate2.GetNameInfo(X509NameType.SimpleName, false) : certificate.Subject;Console.WriteLine("The Common Name for the SSL certificate did not match {0}. Instead, it was {1}.", host, cn);return false;}// The only other errors left are chain errors.Console.WriteLine("The SSL certificate for the server could not be validated for the following reasons:");// The first element's certificate will be the server's SSL certificate (and will match the `certificate` argument)// while the last element in the chain will typically either be the Root Certificate Authority's certificate -or- it// will be a non-authoritative self-signed certificate that the server admin created. foreach (var element in chain.ChainElements){// Each element in the chain will have its own status list. If the status list is empty, it means that the// certificate itself did not contain any errors.if (element.ChainElementStatus.Length == 0)continue;Console.WriteLine("\u2022 {0}", element.Certificate.Subject);foreach (var error in element.ChainElementStatus){// `error.StatusInformation` contains a human-readable error string while `error.Status` is the corresponding enum value.Console.WriteLine("\t\u2022 {0}", error.StatusInformation);}}return false;}/// <summary>/// 发送邮件，带附件/// </summary>/// <param name="title"></param>/// <param name="body"></param>/// <param name="receiver"></param>/// <param name="attachment">附件</param>public void Send(string title, string body, string receiver, System.IO.Stream attachment){SmtpClient _smtpClient = new SmtpClient();_smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;//指定电子邮件发送方式_smtpClient.Host = this.smtpServer; ;//指定SMTP服务器_smtpClient.Credentials = new System.Net.NetworkCredential(this.sender, this.senderPw);//用户名和密码MailMessage _mailMessage = new MailMessage(this.senderMail, receiver);_mailMessage.Subject = title;//主题_mailMessage.Body = body;//内容_mailMessage.BodyEncoding = System.Text.Encoding.UTF8;//正文编码_mailMessage.IsBodyHtml = true;//设置为HTML格式_mailMessage.Priority = MailPriority.High;//优先级Attachment am = new Attachment(attachment, "attachment");_mailMessage.Attachments.Add(am);_smtpClient.Send(_mailMessage);}}
}

测试调用，Program类

using System;
using System.Collections.Generic;
using System.Text;namespace SendMail
{class Program{static void Main(string[] args){Smtp.Mail mail = new Smtp.Mail();mail.Sender = "Test";mail.SenderMail = "Test@mail.com";mail.SenderPw = "Pass@word";mail.SmtpServer = "IP地址";//收件人列表string temp = "test@mail.com;test2@mail.com;";string[] res = temp.Split(';');string content ="邮件内容";for (int i = 0; i < 2; i ++){Console.WriteLine("开始发送第" + i.ToString());mail.Send("邮件测试  " + i.ToString(), content, res);}Console.ReadLine();}}
}