此类的功能包括发送邮件，邮箱格式是否正确，和在不发送邮件的情况下判断邮箱用户名和密码是否正确，鉴于POP检查邮箱用户名和密码出现错误情况返回结果的延迟，用异步线程解决此问题，见代码：

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Net.Mail;using System.Web;using System.Net;using System.Text.RegularExpressions;using System.Net.Sockets;using System.IO;using System.Collections;using System.Threading;namespace Com.Web{ /// <summary> /// 邮箱类 /// </summary> public class CheckEmailInfo { public string server { get; set; }//服务器 public string user { get; set; }//用户名 public string pwd { get; set; }//密码 } /// <summary> /// SendEmail通用类，通过smtp服务器发送邮件 /// </summary> public class SendEmail { public Dictionary<string, string> smtpServer; public Dictionary<string, string> popServer; public SendEmail() { IniSmtpServer(); IniPopServer(); } /// <summary> /// 初始化常用smtpServer，用于绑定下拉选择菜单 /// </summary> private void IniSmtpServer() { smtpServer = new Dictionary<string, string>(); smtpServer.Add("网易163邮箱", "smtp.163.com"); smtpServer.Add("网易vip.163邮箱", "smtp.vip.163.com"); smtpServer.Add("网易126邮箱", "smtp.126.com"); smtpServer.Add("网易188邮箱", "smtp.188.com"); smtpServer.Add("新浪邮箱", "smtp.sina.com"); smtpServer.Add("雅虎邮箱", "smtp.mail.yahoo.com"); smtpServer.Add("搜狐邮箱", "smtp.sohu.com"); smtpServer.Add("TOM邮箱", "smtp.tom.com"); smtpServer.Add("Gmail邮箱", "smtp.gmail.com"); smtpServer.Add("QQ邮箱", "smtp.qq.com"); smtpServer.Add("QQ企业邮箱", "smtp.biz.mail.qq.com"); smtpServer.Add("139邮箱", "smtp.139.com"); smtpServer.Add("263邮箱", "smtp.263.com"); } /// <summary> /// 初始化常用popServer，用于绑定下拉选择菜单 /// </summary> private void IniPopServer() { popServer = new Dictionary<string, string>(); popServer.Add("网易163邮箱", "pop3.163.com"); popServer.Add("网易vip.163邮箱", "pop3.vip.163.com"); popServer.Add("网易126邮箱", "pop3.126.com"); popServer.Add("网易188邮箱", "pop3.188.com"); popServer.Add("新浪邮箱", "pop3.sina.com"); popServer.Add("雅虎邮箱", "pop3.mail.yahoo.com"); popServer.Add("搜狐邮箱", "pop3.sohu.com"); popServer.Add("TOM邮箱", "pop.tom.com"); popServer.Add("Gmail邮箱", "pop.gmail.com"); popServer.Add("QQ邮箱", "pop.qq.com"); popServer.Add("QQ企业邮箱", "pop.biz.mail.qq.com"); popServer.Add("139邮箱", "pop.139.com"); popServer.Add("263邮箱", "pop.263.com"); } /// <summary> /// 发送邮件功能 /// </summary> /// <param name="fromEmail">登录邮箱</param> /// <param name="password">登录密码</param> /// <param name="user">邮件昵称</param> /// <param name="title">邮件标题</param> /// <param name="toEmail">邮件地址</param> /// <param name="email">邮件内容</param> /// <param name="smtpServer">smtp服务器</param> public bool SendMessage(string fromEmail,string password, string user, string title, string toEmail, string email,string smtpServer) { try { 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 smtp.Credentials = new NetworkCredential(fromEmail, password); MailMessage mm = new MailMessage(); //实例化一个邮件类 mm.Priority = MailPriority.High; //邮件的优先级，分为 Low, Normal, High，通常用 Normal即可 mm.From = new MailAddress(fromEmail, user, Encoding.GetEncoding(936)); mm.CC.Add(new MailAddress(toEmail, "", Encoding.GetEncoding(936))); mm.Subject = title; //邮件标题 mm.SubjectEncoding = Encoding.GetEncoding(936); mm.IsBodyHtml = true; //邮件正文是否是HTML格式mm.BodyEncoding = Encoding.GetEncoding(936); mm.Body = email; smtp.Send(mm); return true; } catch { return false; } } /// <summary> /// 检查邮箱是否正确的委托 /// </summary> delegate bool MyDelegate(object checkEmailInfo); /// <summary> /// 利用异步方式检查邮箱账号和密码是否正确 /// </summary> public bool CheckUser(string server, string user, string pwd) { MyDelegate myDelegate = new MyDelegate(CheckUser); CheckEmailInfo checkEmailInfo = new CheckEmailInfo(); checkEmailInfo.server = server; checkEmailInfo.user = user; checkEmailInfo.pwd = pwd; IAsyncResult result = myDelegate.BeginInvoke(checkEmailInfo, null, null); Thread.Sleep(1000);//主线程1秒后检查异步线程是否运行完毕 if (result.IsCompleted) { return myDelegate.EndInvoke(result); }//如果错误的邮箱和密码，函数将会运行很慢 else { return false; } } /// <summary> /// 判断用户邮箱账号和密码是否正确 /// </summary> /// <param name="server">PopServer地址</param> /// <param name="user">用户名</param> /// <param name="pwd">密码</param> private bool CheckUser(object checkEmailInfo) { CheckEmailInfo checkInfo = (CheckEmailInfo)checkEmailInfo; TcpClient sender = new TcpClient(checkInfo.server, 110);//pop协议使用TCP的110端口 Byte[] outbytes; NetworkStream ns; StreamReader sr; string input; string readuser = string.Empty; string readpwd = string.Empty; try { ns = sender.GetStream(); sr = new StreamReader(ns); sr.ReadLine(); //检查用户名和密码 input = "user " + checkInfo.user+ "\r\n"; outbytes = Encoding.ASCII.GetBytes(input.ToCharArray()); ns.Write(outbytes, 0, outbytes.Length); readuser = sr.ReadLine(); input = "pass " + checkInfo.pwd + "\r\n"; outbytes =Encoding.ASCII.GetBytes(input.ToCharArray()); ns.Write(outbytes, 0, outbytes.Length); readpwd = sr.ReadLine(); if (readuser.Substring(0, 3) == "+OK" && readpwd.Substring(0, 3) == "+OK") { return true; } else { return false; } } catch { return false; } } /// <summary> /// 判断邮箱格式是否正确 /// </summary> /// <param name="email">邮箱地址</param> public bool IsEmail(string email) { string paterner = @"\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"; if (!Regex.IsMatch(email, paterner)) { return false;} else {return true;} } }}