怎么样使用c#抓取邮件内容？

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Net;
using System.Net.Sockets;
using System.IO;

namespace MailReceiver
{
/// <summary>
/// Form1 的摘要说明。
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.Label label5;
private System.Windows.Forms.Label label6;
private System.Windows.Forms.TextBox PopServer;
private System.Windows.Forms.TextBox Username;
private System.Windows.Forms.TextBox Password;
private System.Windows.Forms.RichTextBox Message;
private System.Windows.Forms.TextBox MailNum;
private System.Windows.Forms.ListBox Status;
private System.Windows.Forms.Button Connect;
private System.Windows.Forms.Button Disconnect;
private System.Windows.Forms.Button Retrieve;
private System.Windows.Forms.CheckBox BackupChBox;

public TcpClient Server;
public NetworkStream NetStrm;
public StreamReader RdStrm;
public string Data;
public byte[] szData;
public string CRLF = "/r/n";
private System.Windows.Forms.Button BtnExit;
private System.Windows.Forms.Label label7;
private System.Windows.Forms.Label label8;
private System.Windows.Forms.Label label9;
private System.Windows.Forms.Label label10;
private System.Windows.Forms.Label label11;
private System.Windows.Forms.TextBox txtMailFrom;
private System.Windows.Forms.TextBox txtMailCharSet;
private System.Windows.Forms.TextBox txtMailTitle;
private System.Windows.Forms.Label label12;
private System.Windows.Forms.Label label13;
private System.Windows.Forms.RichTextBox txtMailContent;
private System.Windows.Forms.Button btnExplit;
private System.Windows.Forms.TextBox txtMailDate;
private System.Windows.Forms.TextBox txtMailTo;

/// <summary>
/// 必需的设计器变量。
/// </summary>
private System.ComponentModel.Container components = null;

public Form1()
{
//
// Windows 窗体设计器支持所必需的
//
InitializeComponent();

//
// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
//
}

/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}

#region Windows Form Designer generated code
/// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.label3 = new System.Windows.Forms.Label();
this.label4 = new System.Windows.Forms.Label();
this.label5 = new System.Windows.Forms.Label();
this.label6 = new System.Windows.Forms.Label();
this.PopServer = new System.Windows.Forms.TextBox();
this.Username = new System.Windows.Forms.TextBox();
this.Password = new System.Windows.Forms.TextBox();
this.MailNum = new System.Windows.Forms.TextBox();
this.Connect = new System.Windows.Forms.Button();
this.Disconnect = new System.Windows.Forms.Button();
this.Retrieve = new System.Windows.Forms.Button();
this.Message = new System.Windows.Forms.RichTextBox();
this.Status = new System.Windows.Forms.ListBox();
this.BackupChBox = new System.Windows.Forms.CheckBox();
this.BtnExit = new System.Windows.Forms.Button();
this.label7 = new System.Windows.Forms.Label();
this.label8 = new System.Windows.Forms.Label();
this.label9 = new System.Windows.Forms.Label();
this.label10 = new System.Windows.Forms.Label();
this.label11 = new System.Windows.Forms.Label();
this.txtMailFrom = new System.Windows.Forms.TextBox();
this.txtMailDate = new System.Windows.Forms.TextBox();
this.txtMailTitle = new System.Windows.Forms.TextBox();
this.txtMailTo = new System.Windows.Forms.TextBox();
this.txtMailCharSet = new System.Windows.Forms.TextBox();
this.label12 = new System.Windows.Forms.Label();
this.label13 = new System.Windows.Forms.Label();
this.txtMailContent = new System.Windows.Forms.RichTextBox();
this.btnExplit = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// label1
//
this.label1.Location = new System.Drawing.Point(16, 16);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(112, 23);
this.label1.TabIndex = 0;
this.label1.Text = "POP3 服务器地址：";
this.label1.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
//
// label2
//
this.label2.Location = new System.Drawing.Point(16, 48);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(56, 16);
this.label2.TabIndex = 1;
this.label2.Text = "用户名：";
this.label2.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
//
// label3
//
this.label3.Location = new System.Drawing.Point(216, 48);
this.label3.Name = "label3";
this.label3.Size = new System.Drawing.Size(48, 16);
this.label3.TabIndex = 2;
this.label3.Text = "密码：";
this.label3.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
//
// label4
//
this.label4.Location = new System.Drawing.Point(304, 80);
this.label4.Name = "label4";
this.label4.Size = new System.Drawing.Size(72, 23);
this.label4.TabIndex = 3;
this.label4.Text = "邮件编号：";
this.label4.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
//
// label5
//
this.label5.Location = new System.Drawing.Point(16, 80);
this.label5.Name = "label5";
this.label5.Size = new System.Drawing.Size(100, 16);
this.label5.TabIndex = 4;
this.label5.Text = "信息：";
this.label5.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
//
// label6
//
this.label6.Location = new System.Drawing.Point(16, 584);
this.label6.Name = "label6";
this.label6.Size = new System.Drawing.Size(100, 16);
this.label6.TabIndex = 5;
this.label6.Text = "状态：";
this.label6.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
//
// PopServer
//
this.PopServer.Location = new System.Drawing.Point(136, 16);
this.PopServer.Name = "PopServer";
this.PopServer.Size = new System.Drawing.Size(168, 21);
this.PopServer.TabIndex = 0;
this.PopServer.Text = "pop.126.com";
//
// Username
//
this.Username.Location = new System.Drawing.Point(96, 48);
this.Username.Name = "Username";
this.Username.Size = new System.Drawing.Size(104, 21);
this.Username.TabIndex = 1;
this.Username.Text = "Hnxqf222";
//
// Password
//
this.Password.Location = new System.Drawing.Point(280, 48);
this.Password.Name = "Password";
this.Password.PasswordChar = '*';
this.Password.Size = new System.Drawing.Size(104, 21);
this.Password.TabIndex = 2;
this.Password.Text = "iwillwin";
//
// MailNum
//
this.MailNum.Location = new System.Drawing.Point(384, 80);
this.MailNum.Name = "MailNum";
this.MailNum.Size = new System.Drawing.Size(40, 21);
this.MailNum.TabIndex = 4;
this.MailNum.Text = "";
//
// Connect
//
this.Connect.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
this.Connect.Location = new System.Drawing.Point(448, 8);
this.Connect.Name = "Connect";
this.Connect.Size = new System.Drawing.Size(75, 24);
this.Connect.TabIndex = 7;
this.Connect.Text = "连接邮局";
this.Connect.Click += new System.EventHandler(this.Connect_Click);
//
// Disconnect
//
this.Disconnect.Enabled = false;
this.Disconnect.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
this.Disconnect.Location = new System.Drawing.Point(552, 8);
this.Disconnect.Name = "Disconnect";
this.Disconnect.Size = new System.Drawing.Size(75, 24);
this.Disconnect.TabIndex = 8;
this.Disconnect.Text = "断开连接";
this.Disconnect.Click += new System.EventHandler(this.Disconnect_Click);
//
// Retrieve
//
this.Retrieve.Enabled = false;
this.Retrieve.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
this.Retrieve.Location = new System.Drawing.Point(616, 80);
this.Retrieve.Name = "Retrieve";
this.Retrieve.Size = new System.Drawing.Size(72, 24);
this.Retrieve.TabIndex = 9;
this.Retrieve.Text = "收取邮件";
this.Retrieve.Click += new System.EventHandler(this.Retrieve_Click);
//
// Message
//
this.Message.Location = new System.Drawing.Point(8, 112);
this.Message.Name = "Message";
this.Message.ShowSelectionMargin = true;
this.Message.Size = new System.Drawing.Size(704, 136);
this.Message.TabIndex = 3;
this.Message.Text = "";
//
// Status
//
this.Status.HorizontalScrollbar = true;
this.Status.ItemHeight = 12;
this.Status.Location = new System.Drawing.Point(8, 608);
this.Status.Name = "Status";
this.Status.Size = new System.Drawing.Size(704, 136);
this.Status.Sorted = true;
this.Status.TabIndex = 6;
//
// BackupChBox
//
this.BackupChBox.Checked = true;
this.BackupChBox.CheckState = System.Windows.Forms.CheckState.Checked;
this.BackupChBox.Location = new System.Drawing.Point(440, 80);
this.BackupChBox.Name = "BackupChBox";
this.BackupChBox.Size = new System.Drawing.Size(160, 24);
this.BackupChBox.TabIndex = 5;
this.BackupChBox.Text = "在邮件服务器上保留备份";
//
// BtnExit
//
this.BtnExit.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
this.BtnExit.Location = new System.Drawing.Point(648, 8);
this.BtnExit.Name = "BtnExit";
this.BtnExit.Size = new System.Drawing.Size(75, 24);
this.BtnExit.TabIndex = 11;
this.BtnExit.Text = "退出程序";
this.BtnExit.Click += new System.EventHandler(this.BtnExit_Click);
//
// label7
//
this.label7.Location = new System.Drawing.Point(8, 264);
this.label7.Name = "label7";
this.label7.Size = new System.Drawing.Size(64, 23);
this.label7.TabIndex = 12;
this.label7.Text = "发件人：";
//
// label8
//
this.label8.Location = new System.Drawing.Point(8, 296);
this.label8.Name = "label8";
this.label8.Size = new System.Drawing.Size(72, 23);
this.label8.TabIndex = 13;
this.label8.Text = "发信时间：";
//
// label9
//
this.label9.Location = new System.Drawing.Point(8, 328);
this.label9.Name = "label9";
this.label9.Size = new System.Drawing.Size(72, 23);
this.label9.TabIndex = 14;
this.label9.Text = "邮件标题：";
//
// label10
//
this.label10.Location = new System.Drawing.Point(304, 264);
this.label10.Name = "label10";
this.label10.Size = new System.Drawing.Size(72, 23);
this.label10.TabIndex = 15;
this.label10.Text = "收件人：";
//
// label11
//
this.label11.Location = new System.Drawing.Point(304, 296);
this.label11.Name = "label11";
this.label11.Size = new System.Drawing.Size(72, 23);
this.label11.TabIndex = 16;
this.label11.Text = "内容编码：";
//
// txtMailFrom
//
this.txtMailFrom.Location = new System.Drawing.Point(96, 264);
this.txtMailFrom.Name = "txtMailFrom";
this.txtMailFrom.Size = new System.Drawing.Size(184, 21);
this.txtMailFrom.TabIndex = 17;
this.txtMailFrom.Text = "";
//
// txtMailDate
//
this.txtMailDate.Location = new System.Drawing.Point(96, 296);
this.txtMailDate.Name = "txtMailDate";
this.txtMailDate.Size = new System.Drawing.Size(184, 21);
this.txtMailDate.TabIndex = 18;
this.txtMailDate.Text = "";
//
// txtMailTitle
//
this.txtMailTitle.Location = new System.Drawing.Point(96, 328);
this.txtMailTitle.Name = "txtMailTitle";
this.txtMailTitle.Size = new System.Drawing.Size(392, 21);
this.txtMailTitle.TabIndex = 19;
this.txtMailTitle.Text = "";
//
// txtMailTo
//
this.txtMailTo.Location = new System.Drawing.Point(384, 264);
this.txtMailTo.Name = "txtMailTo";
this.txtMailTo.Size = new System.Drawing.Size(184, 21);
this.txtMailTo.TabIndex = 20;
this.txtMailTo.Text = "";
//
// txtMailCharSet
//
this.txtMailCharSet.Location = new System.Drawing.Point(384, 296);
this.txtMailCharSet.Name = "txtMailCharSet";
this.txtMailCharSet.TabIndex = 21;
this.txtMailCharSet.Text = "";
//
// label12
//
this.label12.Location = new System.Drawing.Point(496, 296);
this.label12.Name = "label12";
this.label12.Size = new System.Drawing.Size(72, 23);
this.label12.TabIndex = 22;
this.label12.Text = "邮件长度";
//
// label13
//
this.label13.Location = new System.Drawing.Point(8, 392);
this.label13.Name = "label13";
this.label13.Size = new System.Drawing.Size(80, 16);
this.label13.TabIndex = 24;
this.label13.Text = "邮件内容：";
this.label13.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
//
// txtMailContent
//
this.txtMailContent.Location = new System.Drawing.Point(8, 416);
this.txtMailContent.Name = "txtMailContent";
this.txtMailContent.ShowSelectionMargin = true;
this.txtMailContent.Size = new System.Drawing.Size(704, 152);
this.txtMailContent.TabIndex = 25;
this.txtMailContent.Text = "";
//
// btnExplit
//
this.btnExplit.Enabled = false;
this.btnExplit.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
this.btnExplit.Location = new System.Drawing.Point(624, 264);
this.btnExplit.Name = "btnExplit";
this.btnExplit.Size = new System.Drawing.Size(72, 24);
this.btnExplit.TabIndex = 26;
this.btnExplit.Text = "解析内容";
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(728, 753);
this.Controls.Add(this.btnExplit);
this.Controls.Add(this.txtMailContent);
this.Controls.Add(this.label13);
this.Controls.Add(this.label12);
this.Controls.Add(this.txtMailCharSet);
this.Controls.Add(this.txtMailTo);
this.Controls.Add(this.txtMailTitle);
this.Controls.Add(this.txtMailDate);
this.Controls.Add(this.txtMailFrom);
this.Controls.Add(this.label11);
this.Controls.Add(this.label10);
this.Controls.Add(this.label9);
this.Controls.Add(this.label8);
this.Controls.Add(this.label7);
this.Controls.Add(this.BtnExit);
this.Controls.Add(this.BackupChBox);
this.Controls.Add(this.Status);
this.Controls.Add(this.Message);
this.Controls.Add(this.Retrieve);
this.Controls.Add(this.Disconnect);
this.Controls.Add(this.Connect);
this.Controls.Add(this.MailNum);
this.Controls.Add(this.Password);
this.Controls.Add(this.Username);
this.Controls.Add(this.PopServer);
this.Controls.Add(this.label6);
this.Controls.Add(this.label5);
this.Controls.Add(this.label4);
this.Controls.Add(this.label3);
this.Controls.Add(this.label2);
this.Controls.Add(this.label1);
this.MaximizeBox = false;
this.Name = "Form1";
this.Text = "POP3邮件接收程序";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);

}
#endregion

/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}

private void Connect_Click(object sender, System.EventArgs e)
{
//将光标置为等待状态
Cursor cr = Cursor.Current;
Cursor.Current = Cursors.WaitCursor;

//用110端口新建POP3服务器连接
Server = new TcpClient(PopServer.Text,110);
Status.Items.Clear();

try
{
//初始化
NetStrm = Server.GetStream();
RdStrm= new StreamReader(Server.GetStream());
Status.Items.Add(RdStrm.ReadLine());

//登录服务器过程
Data = "USER "+ Username.Text+CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
Status.Items.Add(RdStrm.ReadLine());

Data = "PASS "+ Password.Text+CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
Status.Items.Add(RdStrm.ReadLine());

//向服务器发送STAT命令，从而取得邮箱的相关信息：邮件数量和大小
Data = "STAT"+CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
Status.Items.Add(RdStrm.ReadLine());

//改变按钮的状态
Connect.Enabled = false;
Disconnect.Enabled = true;
Retrieve.Enabled = true;

//将光标置回原来状态
Cursor.Current = cr;

}
catch(InvalidOperationException err)
{
Status.Items.Add("Error: "+err.ToString());
}
}

private void Disconnect_Click(object sender, System.EventArgs e)
{
//将光标置为等待状态
Cursor cr = Cursor.Current;
Cursor.Current = Cursors.WaitCursor;

//向服务器发送QUIT命令从而结束和POP3服务器的会话
Data = "QUIT"+CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
Status.Items.Add(RdStrm.ReadLine());

//断开连接
NetStrm.Close();
RdStrm.Close();

//改变按钮的状态
Connect.Enabled = true;
Disconnect.Enabled = false;
Retrieve.Enabled = false;

//将光标置回原来状态
Cursor.Current = cr;
}

private void Retrieve_Click(object sender, System.EventArgs e)
{
//将光标置为等待状态
Cursor cr = Cursor.Current;
Cursor.Current = Cursors.WaitCursor;
string szTemp;
string MailContent;
MailContent="";
Message.Clear();

try
{
//根据邮件编号从服务器获得相应邮件
Data = "RETR "+ MailNum.Text+CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
szTemp = RdStrm.ReadLine();
string MailFrom="";
string MailTo="";
string MailTitle="";
string MailDate="";

if(szTemp[0]!='-')
{
//不断地读取邮件内容，只到结束标志：英文句号
int k=0;
while(szTemp!=".")
{
//Message.Text +="第"+i.ToString()+"行"+ szTemp + "/n";
MailContent+=szTemp+"/n";
szTemp = RdStrm.ReadLine();
if (k<10&&k>4)
{
txtMailContent.Text+=k.ToString();
if(szTemp.Substring(0,2).ToLower()=="to")
{
MailTo="发送到"+szTemp.Substring(2,szTemp.Length-2);
}
if(szTemp.Substring(0,4).ToLower()=="from")
{
MailFrom="来自"+szTemp.Substring(4,szTemp.Length-4);
}
if(szTemp.Substring(0,7).ToLower()=="subject")
{
MailTitle="标题"+szTemp.Substring(7,szTemp.Length-7);
}
if(szTemp.Substring(0,4).ToLower()=="date")
{
MailDate+="日期"+szTemp.Substring(4,szTemp.Length-4);
}
}
k=k+1;
}
Message.Text=MailContent;
//txtMailContent=MailContent;
txtMailFrom.Text=MailFrom;
txtMailTo.Text=MailTo;
txtMailTitle.Text=MailTitle;
txtMailDate.Text=MailDate;

//若BackupChBox未选中，则收取邮件后，删除保留在服务器上的邮件
if(BackupChBox.Checked == false)
{
Data = "DELE" + MailNum.Text + CRLF;
szData = System.Text.Encoding.ASCII.GetBytes(Data.ToCharArray());
NetStrm.Write(szData,0,szData.Length);
Status.Items.Add(RdStrm.ReadLine());
}

/*
//解析抓取过来的各种邮件部分
//
//txtMailContent.Clear();

char[] seperator = {'/n'};
string EmailContent;
EmailContent=content.ToString().Trim();
string[] str1 =EmailContent.Split(seperator,10);

for(int i=0;i<=9;i++)
{
//txtMailContent.Text+="/n"+str1.ToString();

/*126邮局的前面9行的内容
+OK 1161 octets
Received: from xqf222 (unknown [222.248.201.237])
by smtp3 (Coremail) with SMTP id wKjSjUpAVAFnNKJE39QhAA==.15858S2;
Wed, 28 Jun 2006 15:48:56 +0800 (CST)
thread-index: Acaah0d07Liy0sFNTsK6weudE0ML7A==
Thread-Topic: =?gb2312?B?1eLA78zu0LS499Pv1tbTyrz+serM4g==?=
From: <csharp222@126.com>
To: <hnxqf222@126.com>
Subject: =?gb2312?B?1eLA78zu0LS499Pv1tbTyrz+serM4g==?=

if(str1.ToString().Trim().Length!=0)
{
txtMailContent.Text+="/n解析内容"+str1.ToString();

if(str1.ToString().Substring(0,2).ToLower()=="to")
{
txtMailContent.Text+="发送到"+str1.ToString().Substring(2,str1.ToString().Length-2);
}
else
{
txtMailContent.Text+="/n没有抓取到收件人信息"+str1.ToString().Substring(0,2).ToLower();
}
if(str1.ToString().Substring(0,4).ToLower()=="from")
{
txtMailContent.Text+="来自"+str1.ToString().Substring(4,str1.ToString().Length-4);
}
else
{
txtMailContent.Text+="/n没有抓取到发件人信息"+str1.ToString().Substring(0,4).ToLower();
}

if(str1.ToString().Substring(0,7).ToLower()=="subject")
{
txtMailContent.Text+="标题"+str1.ToString().Substring(7,str1.ToString().Length-7);
}
else
{
txtMailContent.Text+="/n没有抓取到邮件标题信息"+str1.ToString().Substring(0,7).ToLower();
}

if(str1.ToString().Substring(0,4).ToLower()=="date")
{
txtMailContent.Text+="日期"+str1.ToString().Substring(4,str1.ToString().Length-4);
}
else
{
txtMailContent.Text+="/n没有抓取到邮件日期信息"+str1.ToString().Substring(0,4).ToLower();
}

txtMailContent.Text+="/n循环数组时候结束";
}
else
{
txtMailContent.Text="/n没有抓取到任何数据";
}
}

/*txtMailContent.Text+="内容: "+CRLF;
for(int j=12;j<str1.ToString().Length;j++)
{
if(str1[j].Trim().Length!=0)
{
txtMailContent.Text+=str1[j];
}
}
*/
//

}
else
{
Status.Items.Add(szTemp);
}

//将光标置回原来状态
Cursor.Current = cr;
//解析内容按钮显示
btnExplit.Enabled=true;

}

catch(InvalidOperationException err)
{
Status.Items.Add("Error: "+err.ToString());
}
}

private void BtnExit_Click(object sender, System.EventArgs e)
{
Application.Exit();
}

private void Form1_Load(object sender, System.EventArgs e)
{

}
}
}