C#实现邮件发送，可以添加附件，发件人、收件人信息从xml文件读取

变量：

#region 变量
        private XmlDocument xmlDoc = new XmlDocument();
        private ArrayList toList = new ArrayList();
        private byte key = 123;//加密字
        #region 发件人信息
        private string FJRYXQC = string.Empty;
        private string FJRYXMM = string.Empty;
        private string FJRYXMC = string.Empty;
        private string YXFWQDZ = string.Empty;
        private string FJRXM = string.Empty;
        private string YXFWQPORT = string.Empty;
        #endregion
        #region 收件人信息
        string ACCYXQC = string.Empty;
        string ACCBZ = string.Empty;
        #endregion
        #endregion

发送邮件：

 #region 发送邮件
  
        /// 

        /// 
        /// 
        /// 邮件主题
        /// 邮件内容
        /// 附件路径（附件以字符串的形式存在数组里面）
        public void Send(string theme, string body, string[] FJLJ)
        {
            if (LoadFsrXmlData() && LoadJsrXmlData())
            {
                MailMessage mail = new MailMessage();
                mail.From = new MailAddress(FJRYXQC, FJRXM);
                //发送给谁 
                foreach (String to in toList)
                {
                    mail.To.Add(to);
                }
                //标题 
                mail.Subject = theme;
                //内容编码 
                mail.BodyEncoding = Encoding.Default;
                //发送优先级 
                mail.Priority = MailPriority.High;
                //邮件内容 
                mail.Body = body;
                //是否HTML形式发送 
                mail.IsBodyHtml = true;
                //附件 
                try
                {
                    Attachment data;
                    ContentDisposition disposition;

                    if (FJLJ != null && FJLJ.Length > 0)
                    {
                        foreach (string str in FJLJ)
                        {
                            data = new Attachment(str, MediaTypeNames.Application.Octet);//实例化附件  
                            disposition = data.ContentDisposition;
                            mail.Attachments.Add(data);//添加到附件中 
                        }
                    }
                }
                catch (Exception ex)
                {
                    throw new Exception("添加附件错误！" + ex.Message);
                }
                //邮件服务器和端口号
                int port = int.Parse(YXFWQPORT);
                SmtpClient smtp = new SmtpClient(YXFWQDZ, port);
                //587  
                smtp.UseDefaultCredentials = true;
                //指定发送方式 
                smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
                //指定登录名和密码 
                smtp.Credentials = new System.Net.NetworkCredential(FJRYXMC, FJRYXMM);
                //超时时间 
                smtp.Timeout = 300000;
                smtp.Send(mail);
                MessageBox.Show("发送成功！");
            }
            else
            {
                if (!LoadFsrXmlData()) { 
                    MessageBox.Show("无发件人信息！");
                }

                if (!LoadJsrXmlData())
                {
                    MessageBox.Show("无收件人信息！");
                }
            }
        }
        #endregion

加载fsr.xml文件  读取发送人xml配置文件：

     #region 加载fsr.xml文件  发送人xml配置文件
        public bool LoadFsrXmlData()
        {
            string outMsg = string.Empty;
            try
            {
                string path = Application.StartupPath;
                string folder = System.IO.Path.Combine(path, "config");
                string xmlFileName = System.IO.Path.Combine(folder, "fsr.xml");
                bool folderExists = System.IO.Directory.Exists(folder);
                if (folderExists && File.Exists(xmlFileName))//当文件存在时
                {
                    xmlDoc.Load(xmlFileName);
                    XmlNode root = xmlDoc.SelectSingleNode("root");
                    XmlNodeList nodeList = root.ChildNodes;//获得root节点的子节点
                    foreach (XmlElement xe in nodeList)
                    {
                        FJRYXQC = xe.GetElementsByTagName("FJRYXQC")[0].InnerText;
                        FJRYXMM = encryptDecryptStr(xe.GetElementsByTagName("FJRYXMM")[0].InnerText);
                        FJRYXMC = xe.GetElementsByTagName("FJRYXMC")[0].InnerText;
                        YXFWQDZ = xe.GetElementsByTagName("YXFWQDZ")[0].InnerText;
                        FJRXM = xe.GetElementsByTagName("FJRXM")[0].InnerText;
                        YXFWQPORT = xe.GetElementsByTagName("YXFWQPORT")[0].InnerText;
                    }
                    return true;
                }
                return false;
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("加载config.xml文件失败:" + ex.Message);
                return false;
            }
        }
        #endregion

加载jsr.xml文件 读取接收人xml配置文件：

#region 加载jsr.xml文件 接收人xml配置文件
        public bool LoadJsrXmlData()
        {
            try
            {
                string path = Application.StartupPath;
                string folder = System.IO.Path.Combine(path, "config");
                string xmlFileName = System.IO.Path.Combine(folder, "jsr.xml");
                bool folderExists = System.IO.Directory.Exists(folder);
                if (folderExists && File.Exists(xmlFileName))//当文件存在时
                {
                    xmlDoc.Load(xmlFileName);
                    XmlNode root = xmlDoc.SelectSingleNode("root");
                    XmlNodeList nodeList = root.ChildNodes;//获得root节点的子节点
                    foreach (XmlElement xe in nodeList)
                    {
                        toList.Add(xe.GetElementsByTagName("ACCYXQC")[0].InnerText);
                    }
                    return true;
                }
                return false;
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("加载config.xml文件失败:" + ex.Message);
                return false;
            }
        }
        #endregion

密码加密：

# region 异或加密算法
        public string encryptDecryptStr(string p)
        {
            byte[] bs = Encoding.Default.GetBytes(p);
            for (int i = 0; i < bs.Length; i++)
            {
                bs[i] = (byte)(bs[i] ^ key);
            }
            return Encoding.Default.GetString(bs);
        }
        #endregion