''''**************************
''''检查邮件例子
''''作者：wgscd
'''' qq 153964481
''''*************************
Imports System.Net
Imports System.Net.Sockets
Imports System.IO

Public Class Form1
    Inherits System.Windows.Forms.Form

#Region " Windows 窗体设计器生成的代码 "

    Public Sub New()
        MyBase.New()

        ''''该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

        ''''在 InitializeComponent() 调用之后添加任何初始化

    End Sub

    ''''窗体重写 dispose 以清理组件列表。
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    ''''Windows 窗体设计器所必需的
    Private components As System.ComponentModel.IContainer

    ''''注意: 以下过程是 Windows 窗体设计器所必需的
    ''''可以使用 Windows 窗体设计器修改此过程。
    ''''不要使用代码编辑器修改它。
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents Timer1 As System.Windows.Forms.Timer
    Friend WithEvents ListBox1 As System.Windows.Forms.ListBox
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.components = New System.ComponentModel.Container
        Me.Button1 = New System.Windows.Forms.Button
        Me.Timer1 = New System.Windows.Forms.Timer(Me.components)
        Me.ListBox1 = New System.Windows.Forms.ListBox
        Me.SuspendLayout()
        ''''
        ''''Button1
        ''''
        Me.Button1.BackColor = System.Drawing.Color.FromArgb(CType(192, Byte), CType(192, Byte), CType(255, Byte))
        Me.Button1.FlatStyle = System.Windows.Forms.FlatStyle.Flat
        Me.Button1.Location = New System.Drawing.Point(16, 8)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(104, 40)
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "checkMai"
        ''''
        ''''Timer1
        ''''
        Me.Timer1.Interval = 2000
        ''''
        ''''ListBox1
        ''''
        Me.ListBox1.BackColor = System.Drawing.Color.FromArgb(CType(255, Byte), CType(255, Byte), CType(192, Byte))
        Me.ListBox1.HorizontalScrollbar = True
        Me.ListBox1.ItemHeight = 12
        Me.ListBox1.Location = New System.Drawing.Point(16, 64)
        Me.ListBox1.Name = "ListBox1"
        Me.ListBox1.Size = New System.Drawing.Size(104, 100)
        Me.ListBox1.TabIndex = 2
        ''''
        ''''Form1
        ''''
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.BackColor = System.Drawing.Color.FromArgb(CType(192, Byte), CType(192, Byte), CType(255, Byte))
        Me.ClientSize = New System.Drawing.Size(146, 182)
        Me.Controls.Add(Me.ListBox1)
        Me.Controls.Add(Me.Button1)
        Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedToolWindow
        Me.Name = "Form1"
        Me.Text = "MSG------By wgscd"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Sub checkMail()  
        Dim ip As IPAddress = Dns.GetHostByName(Dns.GetHostName.ToString).AddressList(0)
        Dim ipe As New IPEndPoint(ip, 2345)
        Me.Text = ip.ToString
        Dim tcpc As New TcpClient(ipe)
        tcpc.Connect(Dns.GetHostByName("pop3.126.com").HostName, 110)
        Dim ntstream As NetworkStream
        Dim sr As StreamReader
        Dim sw As StreamWriter
        ntstream = tcpc.GetStream
        Me.ListBox1.Items.Add(ReadFromNetStream(ntstream))
        WriteToNetStream(ntstream, "user wgscd")
        Me.ListBox1.Items.Add(ReadFromNetStream(ntstream))
        WriteToNetStream(ntstream, "pass yourpassword")
        Dim msg As String = ReadFromNetStream(ntstream)
        If msg Like "+OK 0 message*" Then
            MsgBox("No Mail Right now!")
            Me.ListBox1.Items.Add(ReadFromNetStream(ntstream))
        Else
            MsgBox(msg)
            WriteToNetStream(ntstream, "list")
            Me.ListBox1.Items.Add(ReadFromNetStream(ntstream))
        End If
        WriteToNetStream(ntstream, "quit")
        Me.ListBox1.Items.Add(ReadFromNetStream(ntstream))
        tcpc.Close()
    End Sub

    Function ReadFromNetStream(ByRef NetStream As NetworkStream) As String
        Dim bb As Byte() = New Byte(521) {}
        NetStream.Read(bb, 0, bb.Length)
        Dim read As String = System.Text.Encoding.UTF8.GetString(bb)
        Return read
    End Function
    Function WriteToNetStream(ByRef NetStream As NetworkStream, ByVal command As String) As String
        Dim stringToSend As String = command & vbCrLf
        Dim arrayToSend As Byte() = System.Text.Encoding.UTF8.GetBytes(stringToSend.ToCharArray)
        NetStream.Write(arrayToSend, 0, arrayToSend.Length) ''''写入流，不用返回值
    End Function

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim t As New Threading.Thread(AddressOf checkMail)
        t.Start()

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    End Sub
End Class