C#.NET发送邮件的实例代码

using system;
using system.collections.generic;
using system.text;
using system.net.mail;
using system.net;
namespace myquery.utils
{
    /// <summary>
    /// 封装邮件处理
    /// by 贾世义 2011-6-3
    /// </summary>
    public static class mailhelper
    {
        private static string smtphost = null;
        private static int smptport = 25;
        private static bool smtpisusercredentials = false;
        private static string smtpcredentialaccount = null;
        private static string smtpcredentialpassword = null;
        /// <summary>
        /// 设置发送邮件参数
        /// </summary>
        /// <param name="host">smtp服务器地址或名称</param>
        /// <param name="port">smtp服务端口 一般为25</param>
        /// <param name="isusercredentials">是否需要认证</param>
        /// <param name="account">需要认证时的用户</param>
        /// <param name="password">需要认证时的用户的密码</param>
        public static void setparameters(string host, int port, bool isusercredentials, string account, string password)
        {
            smtphost = host;
            smptport = port;
            smtpisusercredentials = isusercredentials;
            smtpcredentialaccount = account;
            smtpcredentialpassword = password;
        }
        /// <summary>
        /// 设置发送邮件参数 取配置
        /// </summary>
        private static void setparameters()
        {
            if (string.isnullorempty(smtphost))
            {
                smtphost = webhelper.getappconfig("smtphost");
                smptport = datahelper.getintvalue(webhelper.getappconfig("smptport"), 25);
                smtpisusercredentials = constants.true_id.equals(webhelper.getappconfig("smtpisusercredentials"));
                smtpcredentialaccount = webhelper.getappconfig("smtpcredentialaccount");
                smtpcredentialpassword = webhelper.getappconfig("smtpcredentialpassword");
            }
        }
        /// <summary>
        /// 发送邮件 发送邮件错误不会抛出异常
        /// </summary>
        /// <param name="receivers">收件人</param>
        /// <param name="title">标题/主题</param>
        /// <param name="content">信件内容</param>
        /// <param name="sender">发件人 空则取系统配置</param>
        public static void sendmail(string receivers, string title, string content, string sender)
        {
            if (!string.isnullorempty(receivers))
            {
                //初始化参数
                setparameters();
                if (!string.isnullorempty(smtphost))
                {
                    try
                    {
                        smtpclient smtp = new smtpclient(smtphost, smptport);
                        if (smtpisusercredentials)
                        {
                            smtp.usedefaultcredentials = true;
                            smtp.credentials = new networkcredential(smtpcredentialaccount, smtpcredentialpassword); ;
                        }
                        smtp.deliverymethod = smtpdeliverymethod.network;
                        if (string.isnullorempty(sender))
                        {
                            sender = smtpcredentialaccount;
                        }
                        foreach (string receiver in datahelper.getstrings(receivers))
                        {
                            mailmessage msg = new mailmessage(sender, receiver, title, content);
                            msg.bodyencoding = encoding.utf8;
                            msg.subjectencoding = encoding.utf8;
                            msg.isbodyhtml = true;
                            smtp.send(msg);
                            msg.dispose();
                        }
                    }
                    catch { }
                }
            }
        }
    }
}