mtpclass.cs

这个类实现了用C#发送邮件的功能

namespace XMMAIL
{
	using System;
	using System.Collections;
	using System.Net.Sockets;
	using System.IO;
	using System.Text;

	/// <summary>
	/// UseSmtp
	/// </summary>
	public class SMTPClass
	{
		/// <summary>
		/// SMTP服务器域名
		/// </summary>
		public string Server 
		{
			get { return server; }
			set { if (value != server) server = value; }
		} private string server = "";

		/// <summary>
		/// SMTP服务器端口 [默认为25]
		/// </summary>
		public int Port 
		{
			get { return port; }
			set { if (value != port) port = value; }
		} private int port = 25;

		/// <summary>
		/// 用户名 [如果需要身份验证的话]
		/// </summary>
		public string UserName 
		{
			get { return userName; }
			set { if (value != userName) userName = value; }
		} private string userName = "";

		/// <summary>
		/// 密码 [如果需要身份验证的话]
		/// </summary>
		public string Password 
		{
			get { return password; }
			set { if (value != password) password = value; }
		} private string password = "";

		/// <summary>
		/// 发件人地址
		/// </summary>
		public string From 
		{
			get { return from; }
			set { if (value != from) from = value;}
		} private string from = "";

		/// <summary>
		/// 收件人地址
		/// </summary>
		public string To 
		{
			get { return to; }
			set { if (value != to) to = value;}
		} private string to = "";

		/// <summary>
		/// 发件人姓名
		/// </summary>
		public string FromName 
		{
			get { return fromName; }
			set { if (value != fromName) fromName = value; }
		} private string fromName = "";

		/// <summary>
		/// 收件人姓名
		/// </summary>
		public string ToName 
		{
			get { return toName; }
			set { if (value != toName) toName = value; }
		} private string toName = "";

		/// <summary>
		/// 邮件的主题
		/// </summary>
		public string Subject 
		{
			get { return subject; }
			set { if (value != subject) subject = value; }
		} private string subject = "";

		/// <summary>
		/// 邮件正文
		/// </summary>
		public string Body 
		{
			get { return body; }
			set { if (value != body) body = value; }
		} private string body = "";

		/// <summary>
		/// 超文本格式的邮件正文
		/// </summary>
		public string HtmlBody 
		{
			get { return htmlBody; }
			set { if (value != htmlBody) htmlBody = value; }
		} private string htmlBody = "";

		/// <summary>
		/// 是否是html格式的邮件
		/// </summary>
		public bool IsHtml 
		{
			get { return isHtml; }
			set { if (value != isHtml) isHtml = value; }
		} private bool isHtml = false;

		/// <summary>
		/// 语言编码 [默认为GB2312]
		/// </summary>
		public string LanguageEncoding 
		{
			get { return languageEncoding; }
			set { if (value != languageEncoding) languageEncoding = value; }
		} private string languageEncoding = "GB2312";

		/// <summary>
		/// 邮件编码 [默认为8bit]
		/// </summary>
		public string MailEncoding 
		{
			get { return encoding; }
			set { if (value != encoding) encoding = value; }
		} private string encoding = "8bit";

		/// <summary>
		/// 邮件优先级 [默认为3]
		/// </summary>
		public int Priority 
		{
			get { return priority; }
			set { if (value != priority) priority = value; }
		} private int priority = 3;

		/// <summary>
		/// 附件 [AttachmentInfo]
		/// </summary>
		public IList Attachments 
		{
			get { return attachments; }
			//   set { if (value != attachments) attachments = value; }
		} private ArrayList attachments = new ArrayList ();


		/// <summary>
		/// 发送邮件
		/// </summary>
		public void SendMail ()
		{
			// 创建TcpClient对象， 并建立连接
			TcpClient tcp = null;
			try
			{
				tcp = new TcpClient (server, port);
			}
			catch (Exception)
			{
				throw new Exception ("无法连接服务器");
			}

			ReadString (tcp.GetStream());//获取连接信息

			// 开始进行服务器认证
			// 如果状态码是250则表示操作成功
			if (!Command (tcp.GetStream(), "EHLO Localhost", "250"))
				throw new Exception ("登陆阶段失败");

			if (userName != "")
			{
				// 需要身份验证
				if (!Command (tcp.GetStream(), "AUTH LOGIN", "334"))
					throw new Exception ("身份验证阶段失败");
				string nameB64 = ToBase64 (userName); // 此处将username转换为Base64码
				if (!Command (tcp.GetStream(), nameB64, "334"))
					throw new Exception ("身份验证阶段失败");
				string passB64 = ToBase64 (password); // 此处将password转换为Base64码
				if (!Command (tcp.GetStream(), passB64, "235"))
					throw new Exception ("身份验证阶段失败");
			}


			// 准备发送
			WriteString (tcp.GetStream(), "mail From: " + from);
			WriteString (tcp.GetStream(), "rcpt to: " + to);
			WriteString (tcp.GetStream(), "data");

			// 发送邮件头
			WriteString (tcp.GetStream(), "Date: " + DateTime.Now); // 时间
			WriteString (tcp.GetStream(), "From: " + fromName + "<" + from + ">"); // 发件人
			WriteString (tcp.GetStream(), "Subject: " + subject); // 主题
			WriteString (tcp.GetStream(), "To:" + toName + "<" + to + ">"); // 收件人

			//邮件格式 
			WriteString (tcp.GetStream(), "Content-Type: multipart/mixed; boundary=\"unique-boundary-1\"");
			WriteString (tcp.GetStream(), "Reply-To:" + from); // 回复地址
			WriteString (tcp.GetStream(), "X-Priority:" + priority); // 优先级
			WriteString (tcp.GetStream(), "MIME-Version:1.0"); // MIME版本

			// 数据ID,随意
			//   WriteString (tcp.GetStream(), "Message-Id: " + DateTime.Now.ToFileTime() + "@security.com");
			WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); // 内容编码
			WriteString (tcp.GetStream(), "X-Mailer:JcPersonal.Utility.MailSender"); // 邮件发送者
			WriteString (tcp.GetStream(), "");

			WriteString (tcp.GetStream(), ToBase64 ("This is a multi-part message in MIME format.")); 
			WriteString (tcp.GetStream(), ""); 

			// 从此处开始进行分隔输入
			WriteString (tcp.GetStream(), "--unique-boundary-1");

			// 在此处定义第二个分隔符
			WriteString (tcp.GetStream(), "Content-Type: multipart/alternative;Boundary=\"unique-boundary-2\"");
			WriteString (tcp.GetStream(), "");

			if(!isHtml)
			{
				// 文本信息
				WriteString (tcp.GetStream(), "--unique-boundary-2");
				WriteString (tcp.GetStream(), "Content-Type: text/plain;charset=" + languageEncoding);
				WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding);
				WriteString (tcp.GetStream(), "");
				WriteString (tcp.GetStream(), body);
				WriteString (tcp.GetStream(), "");//一个部分写完之后就写如空信息，分段
				WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号，尾巴后面多了--
				WriteString (tcp.GetStream(), "");
			}
			else
			{
				//html信息
				WriteString (tcp.GetStream(), "--unique-boundary-2"); 
				WriteString (tcp.GetStream(), "Content-Type: text/html;charset=" + languageEncoding); 
				WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); 
				WriteString (tcp.GetStream(), ""); 
				WriteString (tcp.GetStream(), htmlBody); 
				WriteString (tcp.GetStream(), ""); 
				WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号，尾巴后面多了-- 
				WriteString (tcp.GetStream(), ""); 
			}

			// 发送附件
			// 对文件列表做循环
			for (int i = 0; i < attachments.Count; i++)
			{
				WriteString (tcp.GetStream(), "--unique-boundary-1"); // 邮件内容分隔符
				WriteString (tcp.GetStream(), "Content-Type: application/octet-stream;name=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件格式
				WriteString (tcp.GetStream(), "Content-Transfer-Encoding: base64"); // 内容的编码
				WriteString (tcp.GetStream(), "Content-Disposition:attachment;filename=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件名
				WriteString (tcp.GetStream(), "");
				WriteString (tcp.GetStream(), ((AttachmentInfo)attachments[i]).Bytes); // 写入文件的内容
				WriteString (tcp.GetStream(), "");
			}

			Command (tcp.GetStream(), ".", "250"); // 最后写完了，输入"."

			// 关闭连接
			tcp.Close ();
		}

		/// <summary>
		/// 向流中写入字符
		/// </summary>
		/// <param name="netStream">来自TcpClient的流</param>
		/// <param name="str">写入的字符</param>
		protected void WriteString (NetworkStream netStream, string str)
		{
			str = str + "\r\n"; // 加入换行符

			// 将命令行转化为byte[]
			byte[] bWrite = Encoding.GetEncoding(languageEncoding).GetBytes(str.ToCharArray());

			// 由于每次写入的数据大小是有限制的，那么我们将每次写入的数据长度定在７５个字节，一旦命令长度超过了７５，就分步写入。
			int start=0;
			int length=bWrite.Length;
			int page=0;
			int size=75;
			int count=size;
			try
			{
				if (length>75)
				{
					// 数据分页
					if ((length/size)*size<length)
						page=length/size+1;
					else
						page=length/size;
					for (int i=0;i<page;i++)
					{
						start=i*size;
						if (i==page-1)
							count=length-(i*size);
						netStream.Write(bWrite,start,count);// 将数据写入到服务器上
					}
				}
				else
					netStream.Write(bWrite,0,bWrite.Length);
			}
			catch(Exception)
			{
				// 忽略错误
			}
		}

		/// <summary>
		/// 从流中读取字符
		/// </summary>
		/// <param name="netStream">来自TcpClient的流</param>
		/// <returns>读取的字符</returns>
		protected string ReadString (NetworkStream netStream)
		{
			string sp = null;
			byte[] by = new byte[1024];
			int size = netStream.Read(by,0,by.Length);// 读取数据流
			if (size > 0)
			{
				sp = Encoding.Default.GetString(by);// 转化为String
			}
			return sp;
		}

		/// <summary>
		/// 发出命令并判断返回信息是否正确
		/// </summary>
		/// <param name="netStream">来自TcpClient的流</param>
		/// <param name="command">命令</param>
		/// <param name="state">正确的状态码</param>
		/// <returns>是否正确</returns>
		protected bool Command (NetworkStream netStream, string command, string state)
		{
			string sp=null;
			bool success=false;
			try
			{
				WriteString (netStream, command);// 写入命令
				sp = ReadString (netStream);// 接受返回信息
				if (sp.IndexOf(state) != -1)// 判断状态码是否正确
					success=true;
			}
			catch(Exception)
			{
				// 忽略错误
			}
			return success;
		}

		/// <summary>
		/// 字符串编码为Base64
		/// </summary>
		/// <param name="str">字符串</param>
		/// <returns>Base64编码的字符串</returns>
		protected string ToBase64 (string str)
		{
			try
			{
				byte[] by = Encoding.Default.GetBytes (str.ToCharArray());
				str = Convert.ToBase64String (by);
			}
			catch(Exception)
			{
				// 忽略错误
			}
			return str;
		}

		/// <summary>
		/// 附件信息
		/// </summary>
		public struct AttachmentInfo
		{
			/// <summary>
			/// 附件的文件名 [如果输入路径，则自动转换为文件名]
			/// </summary>
			public string FileName 
			{
				get { return fileName; }
				set { fileName = Path.GetFileName(value); }
			} private string fileName;

			/// <summary>
			/// 附件的内容 [由经Base64编码的字节组成]
			/// </summary>
			public string Bytes 
			{
				get { return bytes; }
				set { if (value != bytes) bytes = value; }
			} private string bytes;

			/// <summary>
			/// 从流中读取附件内容并构造
			/// </summary>
			/// <param name="ifileName">附件的文件名</param>
			/// <param name="stream">流</param>
			public AttachmentInfo (string ifileName, Stream stream)
			{
				fileName = Path.GetFileName (ifileName);
				byte[] by = new byte [stream.Length];
				stream.Read (by,0,(int)stream.Length); // 读取文件内容
				//格式转换
				bytes = Convert.ToBase64String (by); // 转化为base64编码
			}

			/// <summary>
			/// 按照给定的字节构造附件
			/// </summary>
			/// <param name="ifileName">附件的文件名</param>
			/// <param name="ibytes">附件的内容 [字节]</param>
			public AttachmentInfo (string ifileName, byte[] ibytes)
			{
				fileName = Path.GetFileName (ifileName);
				bytes = Convert.ToBase64String (ibytes); // 转化为base64编码
			}

			/// <summary>
			/// 从文件载入并构造
			/// </summary>
			/// <param name="path"></param>
			public AttachmentInfo (string path)
			{
				fileName = Path.GetFileName (path);
				FileStream file = new FileStream (path, FileMode.Open);
				byte[] by = new byte [file.Length];
				file.Read (by,0,(int)file.Length); // 读取文件内容
				//格式转换
				bytes = Convert.ToBase64String (by); // 转化为base64编码
				file.Close ();
			}
		}
	}
}