救命啊！那位高手懂得用TcpClient类来实现smtp邮件的发送阿？

Question

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Net.Sockets;
using System.Net;
using System.Text;
using System.IO;
using System.Text.RegularExpressions;namespace MailClient
{
/// <summary>
/// Summary description for Form1.
/// </summary>
public class MailForm : System.Windows.Forms.Form
{
private System.Windows.Forms.TabControl tabControl1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Button btnReceive;
private System.Windows.Forms.TextBox txtPopServer;
private System.Windows.Forms.TextBox txtUserName;
private System.Windows.Forms.TextBox txtPassword;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.TabPage recvTab;
private System.Windows.Forms.TabPage sendTab;
private System.Windows.Forms.Button btnSend;
private System.Windows.Forms.TextBox txtSubject;
private System.Windows.Forms.TextBox txtTo;
private System.Windows.Forms.TextBox txtFrom;
private System.Windows.Forms.TextBox txtSmtpServer;
private System.Windows.Forms.Label label6;
private System.Windows.Forms.Label labelSubject;
private System.Windows.Forms.Label labelTo;
private System.Windows.Forms.Label labelFrom;
private System.Windows.Forms.Label labelServer;
private System.Windows.Forms.ListBox lstLog;
private System.Windows.Forms.ListBox lstLog2;
private System.Windows.Forms.TextBox txtMessage;
private System.Windows.Forms.TextBox txtEmails;
private System.Windows.Forms.Label label5;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.Container components = null; public MailForm()
{
//
// Required for Windows Form Designer support
//
InitializeComponent(); //
// TODO: Add any constructor code after InitializeComponent call
//
} /// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null) 
{
components.Dispose();
}
}
base.Dispose( disposing );
} #region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.tabControl1 = new System.Windows.Forms.TabControl();
this.sendTab = new System.Windows.Forms.TabPage();
this.lstLog = new System.Windows.Forms.ListBox();
this.btnSend = new System.Windows.Forms.Button();
this.txtMessage = new System.Windows.Forms.TextBox();
this.txtSubject = new System.Windows.Forms.TextBox();
this.txtTo = new System.Windows.Forms.TextBox();
this.txtFrom = new System.Windows.Forms.TextBox();
this.txtSmtpServer = new System.Windows.Forms.TextBox();
this.label6 = new System.Windows.Forms.Label();
this.labelSubject = new System.Windows.Forms.Label();
this.labelTo = new System.Windows.Forms.Label();
this.labelFrom = new System.Windows.Forms.Label();
this.labelServer = new System.Windows.Forms.Label();
this.recvTab = new System.Windows.Forms.TabPage();
this.txtEmails = new System.Windows.Forms.TextBox();
this.lstLog2 = new System.Windows.Forms.ListBox();
this.label4 = new System.Windows.Forms.Label();
this.txtPassword = new System.Windows.Forms.TextBox();
this.txtUserName = new System.Windows.Forms.TextBox();
this.txtPopServer = new System.Windows.Forms.TextBox();
this.btnReceive = new System.Windows.Forms.Button();
this.label1 = new System.Windows.Forms.Label();
this.label3 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.label5 = new System.Windows.Forms.Label();
this.tabControl1.SuspendLayout();
this.sendTab.SuspendLayout();
this.recvTab.SuspendLayout();
this.SuspendLayout();
// 
// tabControl1
// 
this.tabControl1.Controls.AddRange(new System.Windows.Forms.Control[] {
  this.sendTab,
  this.recvTab});
this.tabControl1.Location = new System.Drawing.Point(0, 8);
this.tabControl1.Name = "tabControl1";
this.tabControl1.SelectedIndex = 0;
this.tabControl1.Size = new System.Drawing.Size(408, 360);
this.tabControl1.TabIndex = 0;
// 
// sendTab
// 
this.sendTab.Controls.AddRange(new System.Windows.Forms.Control[] {
  this.label5,
  this.lstLog,
  this.btnSend,
  this.txtMessage,
  this.txtSubject,
  this.txtTo,
  this.txtFrom,
  this.txtSmtpServer,
  this.label6,
  this.labelSubject,
  this.labelTo,
  this.labelFrom,
  this.labelServer});
this.sendTab.Location = new System.Drawing.Point(4, 22);
this.sendTab.Name = "sendTab";
this.sendTab.Size = new System.Drawing.Size(400, 334);
this.sendTab.TabIndex = 0;
this.sendTab.Text = "Send";
// 
// lstLog
// 
this.lstLog.Location = new System.Drawing.Point(8, 120);
this.lstLog.Name = "lstLog";
this.lstLog.Size = new System.Drawing.Size(384, 82);
this.lstLog.TabIndex = 11;
// 
// btnSend
// 
this.btnSend.Location = new System.Drawing.Point(312, 304);
this.btnSend.Name = "btnSend";
this.btnSend.TabIndex = 5;
this.btnSend.Text = "&Send";
this.btnSend.Click += new System.EventHandler(this.btnSend_Click);
// 
// txtMessage
// 
this.txtMessage.Location = new System.Drawing.Point(8, 224);
this.txtMessage.Multiline = true;
this.txtMessage.Name = "txtMessage";
this.txtMessage.Size = new System.Drawing.Size(384, 80);
this.txtMessage.TabIndex = 4;
this.txtMessage.Text = "";
// 
// txtSubject
// 
this.txtSubject.Location = new System.Drawing.Point(88, 80);
this.txtSubject.Name = "txtSubject";
this.txtSubject.Size = new System.Drawing.Size(296, 20);
this.txtSubject.TabIndex = 3;
this.txtSubject.Text = "";
// 
// txtTo
// 
this.txtTo.Location = new System.Drawing.Point(88, 56);
this.txtTo.Name = "txtTo";
this.txtTo.Size = new System.Drawing.Size(296, 20);
this.txtTo.TabIndex = 2;
this.txtTo.Text = "";
// 
// txtFrom
// 
this.txtFrom.Location = new System.Drawing.Point(88, 32);
this.txtFrom.Name = "txtFrom";
this.txtFrom.Size = new System.Drawing.Size(296, 20);
this.txtFrom.TabIndex = 1;
this.txtFrom.Text = "";
// 
// txtSmtpServer
// 
this.txtSmtpServer.Location = new System.Drawing.Point(88, 8);
this.txtSmtpServer.Name = "txtSmtpServer";
this.txtSmtpServer.Size = new System.Drawing.Size(296, 20);
this.txtSmtpServer.TabIndex = 0;
this.txtSmtpServer.Text = "";
// 
// label6
// 
this.label6.AutoSize = true;
this.label6.Location = new System.Drawing.Point(8, 208);

Answer 1

this.label6.Name = "label6";
this.label6.Size = new System.Drawing.Size(95, 13);
this.label6.TabIndex = 4;
this.label6.Text = "Message to Send:";
// 
// labelSubject
// 
this.labelSubject.AutoSize = true;
this.labelSubject.Location = new System.Drawing.Point(8, 80);
this.labelSubject.Name = "labelSubject";
this.labelSubject.Size = new System.Drawing.Size(45, 13);
this.labelSubject.TabIndex = 3;
this.labelSubject.Text = "Subject:";
// 
// labelTo
// 
this.labelTo.AutoSize = true;
this.labelTo.Location = new System.Drawing.Point(8, 56);
this.labelTo.Name = "labelTo";
this.labelTo.Size = new System.Drawing.Size(21, 13);
this.labelTo.TabIndex = 2;
this.labelTo.Text = "To:";
// 
// labelFrom
// 
this.labelFrom.AutoSize = true;
this.labelFrom.Location = new System.Drawing.Point(8, 32);
this.labelFrom.Name = "labelFrom";
this.labelFrom.Size = new System.Drawing.Size(34, 13);
this.labelFrom.TabIndex = 1;
this.labelFrom.Text = "From:";
// 
// labelServer
// 
this.labelServer.AutoSize = true;
this.labelServer.Location = new System.Drawing.Point(8, 8);
this.labelServer.Name = "labelServer";
this.labelServer.Size = new System.Drawing.Size(70, 13);
this.labelServer.TabIndex = 0;
this.labelServer.Text = "Smtp Server:";
// 
// recvTab
// 
this.recvTab.Controls.AddRange(new System.Windows.Forms.Control[] {
  this.txtEmails,
  this.lstLog2,
  this.label4,
  this.txtPassword,
  this.txtUserName,
  this.txtPopServer,
  this.btnReceive,
  this.label1,
  this.label3,
  this.label2});
this.recvTab.Location = new System.Drawing.Point(4, 22);
this.recvTab.Name = "recvTab";
this.recvTab.Size = new System.Drawing.Size(400, 334);
this.recvTab.TabIndex = 1;
this.recvTab.Text = "Receive";
// 
// txtEmails
// 
this.txtEmails.Location = new System.Drawing.Point(8, 208);
this.txtEmails.Multiline = true;
this.txtEmails.Name = "txtEmails";
this.txtEmails.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
this.txtEmails.Size = new System.Drawing.Size(376, 88);
this.txtEmails.TabIndex = 4;
this.txtEmails.Text = "";
// 
// lstLog2
// 
this.lstLog2.Location = new System.Drawing.Point(8, 88);
this.lstLog2.Name = "lstLog2";
this.lstLog2.Size = new System.Drawing.Size(376, 95);
this.lstLog2.TabIndex = 11;
// 
// label4
// 
this.label4.AutoSize = true;
this.label4.Location = new System.Drawing.Point(8, 192);
this.label4.Name = "label4";
this.label4.Size = new System.Drawing.Size(59, 13);
this.label4.TabIndex = 9;
this.label4.Text = "Messages:";
// 
// txtPassword
// 
this.txtPassword.Location = new System.Drawing.Point(72, 56);
this.txtPassword.Name = "txtPassword";
this.txtPassword.PasswordChar = '*';
this.txtPassword.Size = new System.Drawing.Size(312, 20);
this.txtPassword.TabIndex = 2;
this.txtPassword.Text = "";
// 
// txtUserName
// 
this.txtUserName.Location = new System.Drawing.Point(72, 32);
this.txtUserName.Name = "txtUserName";
this.txtUserName.Size = new System.Drawing.Size(312, 20);
this.txtUserName.TabIndex = 1;
this.txtUserName.Text = "";
// 
// txtPopServer
// 
this.txtPopServer.Location = new System.Drawing.Point(72, 8);
this.txtPopServer.Name = "txtPopServer";
this.txtPopServer.Size = new System.Drawing.Size(312, 20);
this.txtPopServer.TabIndex = 0;
this.txtPopServer.Text = "";
// 
// btnReceive
// 
this.btnReceive.Location = new System.Drawing.Point(312, 304);
this.btnReceive.Name = "btnReceive";
this.btnReceive.TabIndex = 3;
this.btnReceive.Text = "&Receive";
this.btnReceive.Click += new System.EventHandler(this.btnReceive_Click);
// 
// label1
// 
this.label1.AutoSize = true;
this.label1.Location = new System.Drawing.Point(8, 56);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(57, 13);
this.label1.TabIndex = 3;
this.label1.Text = "Password:";
// 
// label3
// 
this.label3.AutoSize = true;
this.label3.Location = new System.Drawing.Point(8, 8);
this.label3.Name = "label3";
this.label3.Size = new System.Drawing.Size(64, 13);
this.label3.TabIndex = 2;
this.label3.Text = "POP Server";
// 
// label2
// 
this.label2.AutoSize = true;
this.label2.Location = new System.Drawing.Point(8, 32);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(61, 13);
this.label2.TabIndex = 1;
this.label2.Text = "UserName:";
// 
// label5
// 
this.label5.AutoSize = true;
this.label5.Location = new System.Drawing.Point(8, 104);
this.label5.Name = "label5";
this.label5.Size = new System.Drawing.Size(94, 13);
this.label5.TabIndex = 12;
this.label5.Text = "Status Messages:";
// 
// MailForm
// 
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(408, 365);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
  this.tabControl1});
this.Name = "MailForm";
this.Text = "Email Client";
this.tabControl1.ResumeLayout(false);
this.sendTab.ResumeLayout(false);
this.recvTab.ResumeLayout(false);
this.ResumeLayout(false); }
#endregion

Answer 2

/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main() 
{
Application.Run(new MailForm());
} private void btnSend_Click(object sender, System.EventArgs e)
{
// change the cursor to hourglass
Cursor appCursor = Cursor.Current;
Cursor.Current = Cursors.WaitCursor;

string sendString; byte [] dataToSend; string receiveData; try
{
// creating an instance of the TcpClient class
TcpClient smtpServer = new TcpClient(txtSmtpServer.Text, 25);

lstLog.Items.Add("Connection Established with " + txtSmtpServer.Text);

// creating stream classes for communication
NetworkStream writeStream = smtpServer.GetStream();
StreamReader readStream = new StreamReader(smtpServer.GetStream());

// receiving connection success
receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData); // sending From Email Address
sendString = "MAIL FROM: " + "<" + txtFrom.Text + ">\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData);
                
// sending To Email Address
sendString = "RCPT TO: " + "<" + txtTo.Text + ">\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData); // sending data
sendString = "DATA " + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData);

// sending Message Subject and Text
sendString = "SUBJECT: " + txtSubject.Text + "\r\n" + txtMessage.Text + "\r\n" + "." + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData); // sending Disconnect from Server
sendString = "QUIT " + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog.Items.Add(receiveData); // closing all open resources
writeStream.Close();
readStream.Close(); smtpServer.Close();
}
catch(SocketException se)
{
MessageBox.Show("SocketException:" + se.ToString());
}
catch(Exception excep)
{
MessageBox.Show("Exception:" + excep.ToString());
} // restoring the cursor state
Cursor.Current = appCursor; } private void btnReceive_Click(object sender, System.EventArgs e)
{ // change the cursor to hourglass
Cursor appCursor = Cursor.Current;
Cursor.Current = Cursors.WaitCursor;

string sendString; byte [] dataToSend; string receiveData; try
{
TcpClient popServer = new TcpClient(txtPopServer.Text,110);

NetworkStream writeStream = popServer.GetStream();
StreamReader readStream = new StreamReader(popServer.GetStream()); // connect with the server
receiveData = readStream.ReadLine();
lstLog2.Items.Add(receiveData); // sending username to the server
sendString = "USER " + txtUserName.Text + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog2.Items.Add(receiveData); // sending password to the server
sendString = "PASS " + txtPassword.Text + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog2.Items.Add(receiveData); // getting the number of emails on the server
sendString = "STAT" + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog2.Items.Add(receiveData);

// parse the returned number into integer
Match m = Regex.Match(receiveData,@"(\s\d*\s)");
int nMails = 0; if (m.Success)
{
nMails = int.Parse(m.ToString());
} // reading emails in a loop


for (int index = 1; index <= nMails; index++)
{
string szTemp; // reading individual email
MessageBox.Show("Reading Email:" + index.ToString());
sendString = "RETR " + index.ToString() + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
szTemp = receiveData;

while(receiveData != ".")
{
receiveData = readStream.ReadLine();
szTemp = szTemp + "\r\n" + receiveData;
}

txtEmails.Text = txtEmails.Text + 
index.ToString() + "\r\n" + 
szTemp + "\r\n";
//lstMsgList.Items.Add(receiveData); }

// Disconnect from the server
sendString = "QUIT" + "\r\n";
dataToSend = Encoding.ASCII.GetBytes(sendString);
writeStream.Write(dataToSend,0,dataToSend.Length); receiveData = readStream.ReadLine();
lstLog2.Items.Add(receiveData); // freeing all open resources
writeStream.Close();
readStream.Close();

popServer.Close();
}
catch(SocketException se)
{
MessageBox.Show("SocketException:" + se.ToString());
}
catch(Exception excep)
{
MessageBox.Show("Exception:" + excep.ToString());
} // restoring the cursor state
Cursor.Current = appCursor; }
}
}

Answer 3

谢谢rwdx
不过我的第一种方法的代码也是这样的
关键问题在下面这句代码：TcpClient smtpServer = new TcpClient(txtSmtpServer.Text, 25);即在文本控件txtSmtpServer里，输入的服务器应该是没有smtp认证就可以用的服务器
应为这个TcpClient类不支持smtp认证，
所以我就想能不能用我自己系统提供的iis里smtp服务作为服务器，但是不行