System.Web.Mail.MailMessage mail = new System.Web.Mail.MailMessage();
mail.To = "收件箱";
mail.From = "发件箱";
mail.Subject = "邮件标题";
mail.BodyFormat = System.Web.Mail.MailFormat.Html;
mail.Body = "邮件内容";
mail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", "1");
mail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", "发件箱");
mail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword", "发件箱密码");
mail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserverport", 465);
mail.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpusessl", "true");
System.Web.Mail.SmtpMail.SmtpServer = "smtp.exmail.qq.com";//邮件服务器
System.Web.Mail.SmtpMail.Send(mail);