C# 发送邮件

using System.Net.Mail;

using System.Net;

using System.Text;

protected void Button1_Click(object sender, EventArgs e)    {        try        {            //实例化SmtpClient            SmtpClient client = new SmtpClient("pop.qq.com", 25);            //出站方式设置为NetWork            client.DeliveryMethod = SmtpDeliveryMethod.Network;            //smtp服务器验证并制定账号密码            client.Credentials = new NetworkCredential("[e-mail]", "******");            MailMessage message = new MailMessage();            //设置优先级            message.Priority = MailPriority.Normal;            //设置收件方看到的邮件来源为:发送方邮件地址、来源标题、编码            message.From = new MailAddress("[e-mail]", "xxx", Encoding.GetEncoding("gb2312"));            //接收方            message.To.Add("[e-mail]");            //标题            message.Subject = "This is 标题";            message.SubjectEncoding = Encoding.GetEncoding("gb2312");            //邮件正文是否支持HTML            message.IsBodyHtml = true;            //正文编码            message.BodyEncoding = Encoding.GetEncoding("gb2312");            message.Body = "<font color='red'>这是一封使用C#网页发送的电子邮件！请勿回复！测试</font><br/>";            client.Send(message);        }        catch (System.Exception ex)        {            Response.Write(ex.Message);        }    }

//超时，默认100s
                client.Timeout = 100000;

//附件列表

message.Attachments.Add(new Attachment("E:\\a.txt"));

webconfig 设置超时60s

<system.web>

<httpRuntime maxRequestLength="1000000" executionTimeout="60000" />

</system.web>