c# 发邮件

using System;
using System.Collections.Generic;
using System.Text;
using System.Configuration;
using System.IO;
using System.Web;
using System.Net.Mail;
using System.Net;
using System.ComponentModel;

namespace EasyFrame.Common
{
    public class GTMail
    {
        #region 发送电子邮件
        /// <summary>
        /// 发送电子邮件
        /// </summary>
        /// <param name="smtpserver">SMTP服务器</param>
        /// <param name="userName">登录帐号</param>
        /// <param name="pwd">登录密码</param>
        /// <param name="nickName">发件人昵称</param>
        /// <param name="strfrom">发件人</param>
        /// <param name="strto">收件人</param>
        /// <param name="subj">主题</param>
        /// <param name="bodys">内容</param>
        public static void sendMail(string smtpserver, string userName, string pwd, string nickName, string strfrom, string strto, string subj, string bodys)
        {
            SmtpClient _smtpClient = new SmtpClient();
            _smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;//指定电子邮件发送方式
            _smtpClient.Host = smtpserver;//指定SMTP服务器
            _smtpClient.Credentials = new System.Net.NetworkCredential(userName, pwd);//用户名和密码

            //MailMessage _mailMessage = new MailMessage(strfrom, strto);
            MailAddress _from = new MailAddress(strfrom, nickName);
            MailAddress _to = new MailAddress(strto);
            MailMessage _mailMessage = new MailMessage(_from, _to);
            _mailMessage.Subject = subj;//主题
            _mailMessage.Body = bodys;//内容
            _mailMessage.BodyEncoding = System.Text.Encoding.Default;//正文编码
            _mailMessage.IsBodyHtml = true;//设置为HTML格式
            _mailMessage.Priority = MailPriority.Normal;//优先级
            _smtpClient.Send(_mailMessage);
        }
        #endregion

        #region 简单电子邮件发送
        /// <summary>
        /// 简单电子邮件发送
        /// </summary>
        /// <param name="smtpserver">SMTP服务器</param>
        /// <param name="userName">登录帐号</param>
        /// <param name="pwd">登录密码</param>
        /// <param name="nickName">发件人昵称</param>
        /// <param name="mailFrom">发件人</param>
        /// <param name="mailTo">收件人</param>
        /// <param name="subj">主题</param>
        /// <param name="bodys">内容</param>
        public static void sendMail(string smtpserver, int smtpport, string userName, string pwd, string nickName, string mailFrom, string mailTo, string subj, string bodys)
        {
            SmtpClient _smtpClient = new SmtpClient();
            _smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;//指定电子邮件发送方式
            _smtpClient.Host = smtpserver;//指定SMTP服务器
            _smtpClient.Port = smtpport;
            _smtpClient.EnableSsl = true;
            //_smtpClient.SendCompleted += new SendCompletedEventHandler(Smtp_SendCompleted);
            _smtpClient.Credentials = new NetworkCredential(userName, pwd);//用户名和密码    
            MailAddress _from = new MailAddress(mailFrom, nickName, Encoding.GetEncoding(936));
            MailAddress _to = new MailAddress(mailTo);
            MailMessage _mailMessage = new MailMessage(_from, _to);
            _mailMessage.Subject = subj;//主题
            _mailMessage.Body = bodys;//内容
            _mailMessage.BodyEncoding = Encoding.Default;//正文编码
            _mailMessage.IsBodyHtml = true;//设置为HTML格式
            _mailMessage.Priority = MailPriority.Normal;//优先级
            _smtpClient.Send(_mailMessage);
            //_smtpClient.SendMailAsync(_mailMessage);
        }

        private static void Smtp_SendCompleted(object sender, AsyncCompletedEventArgs e)
        {
            string msg = e.UserState.ToString();
            SmtpClient smtp = (SmtpClient)sender;
            if (e.Error == null)//问题出现后，这里的Error并没有错误
            {
                msg += ",1";//发送成功
            }
            else
            {
                msg += ",0";
                smtp.SendAsyncCancel();
            }
        }
        #endregion

        #region 邮件批量发送
        /// <summary>
        /// 邮件批量发送
        /// </summary>
        /// <param name="smtpserver"></param>
        /// <param name="smtpport"></param>
        /// <param name="userName"></param>
        /// <param name="pwd"></param>
        /// <param name="mailFrom"></param>
        /// <param name="nickName"></param>
        /// <param name="mailTo"></param>
        /// <param name="subj"></param>
        /// <param name="bodys"></param>
        /// <param name="cc"></param>
        /// <param name="bcc"></param>
        /// <param name="mailAttachments"></param>
        public static void SendMail(string smtpserver, int smtpport, string userName, string pwd, string mailFrom, string nickName, string[] mailTo, string subj, string bodys, string[] cc, string[] bcc, string[] mailAttachments)
        {
            SmtpClient smtp = new SmtpClient(); //实例化一个SmtpClient
            smtp.DeliveryMethod = SmtpDeliveryMethod.Network; //将smtp的出站方式设为 Network
            smtp.EnableSsl = false;//smtp服务器是否启用SSL加密
            smtp.Host = smtpserver; //指定 smtp 服务器地址
            smtp.Port = smtpport;             //指定 smtp 服务器的端口，默认是25，如果采用默认端口，可省去
                                              //如果你的SMTP服务器不需要身份认证，则使用下面的方式，不过，目前基本没有不需要认证的了
            smtp.UseDefaultCredentials = true;
            //smtp.SendCompleted += new SendCompletedEventHandler(Smtp_SendCompleted);
            //如果需要认证，则用下面的方式
            smtp.Credentials = new NetworkCredential(userName, pwd);
            MailMessage mm = new MailMessage(); //实例化一个邮件类
            mm.Priority = MailPriority.Normal; //邮件的优先级，分为 Low, Normal, High，通常用 Normal即可
            mm.From = new MailAddress(mailFrom, nickName, Encoding.GetEncoding(936));
            //收件方看到的邮件来源；
            //第一个参数是发信人邮件地址
            //第二参数是发信人显示的名称
            //第三个参数是 第二个参数所使用的编码，如果指定不正确，则对方收到后显示乱码
            //936是简体中文的codepage值
            //注：上面的邮件来源，一定要和你登录邮箱的帐号一致，否则会认证失败

            mm.ReplyToList.Add(mailFrom);
            //ReplyTo 表示对方回复邮件时默认的接收地址，即：你用一个邮箱发信，但却用另一个来收信

            if (cc.Length > 0)
            {
                mm.CC.Add(string.Join(",", cc));//抄送  
            }
            if (bcc.Length > 0)
            {
                mm.Bcc.Add(string.Join(",", bcc));//密送
            }
            if (mailAttachments.Length > 0)
            {
                for (int i = 0; i < mailAttachments.Length; i++)
                {
                    Attachment objMailAttachment = new Attachment(@mailAttachments[i]);//发送邮件的附件的地址
                    mm.Attachments.Add(objMailAttachment);//将附件附加到邮件消息对象中 
                }
            }
            mm.To.Add(string.Join(",", mailTo));
            mm.Subject = subj; //邮件标题
            mm.SubjectEncoding = Encoding.GetEncoding(936);
            // 这里非常重要，如果你的邮件标题包含中文，这里一定要指定，否则对方收到的极有可能是乱码。
            // 936是简体中文的pagecode，如果是英文标题，这句可以忽略不用
            mm.IsBodyHtml = true; //邮件正文是否是HTML格式

            mm.BodyEncoding = Encoding.GetEncoding(936);
            //邮件正文的编码， 设置不正确， 接收者会收到乱码

            mm.Body = bodys;
            //邮件正文
            smtp.Send(mm);
            //smtp.SendMailAsync(mm); //发送邮件，如果不返回异常， 则大功告成了。
        }
        #endregion 
    }
}