HOWTO?: FTPing with System.Net.Sockets.Socket

[Nigh™a®e]

Hi,

I'm creating a little multithreaded FTP Client. I used to do this with the INET API functions. Now i want to try it with sockects in VB.NET. I can connect and execute some commands on the server but the LIST command or transfering files doesnt work.

I tryed different ways to find the solution for this.
Changing the Socket / Stream Options doesnt help.


Imports System.Net
Imports System.Net.Sockets

Public Class Form1
Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

Public Sub New()
MyBase.New()

'This call is required by the Windows Form Designer.
InitializeComponent()

'Add any initialization after the InitializeComponent() call

End Sub

'Form overrides dispose to clean up the component list.
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

'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer

'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
Friend WithEvents Button2 As System.Windows.Forms.Button
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button()
Me.TextBox1 = New System.Windows.Forms.TextBox()
Me.Button2 = New System.Windows.Forms.Button()
Me.SuspendLayout()
'
'Button1
'
Me.Button1.Location = New System.Drawing.Point(184, 168)
Me.Button1.Name = "Button1"
Me.Button1.TabIndex = 0
Me.Button1.Text = "Button1"
'
'TextBox1
'
Me.TextBox1.Location = New System.Drawing.Point(208, 240)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.TabIndex = 1
Me.TextBox1.Text = "TextBox1"
'
'Button2
'
Me.Button2.Location = New System.Drawing.Point(224, 272)
Me.Button2.Name = "Button2"
Me.Button2.TabIndex = 2
Me.Button2.Text = "Button2"
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(584, 437)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.Button2, Me.TextBox1, Me.Button1})
Me.Name = "Form1"
Me.Text = "Form1"
Me.ResumeLayout(False)

End Sub

#End Region

Private _FTPConn As Socket
Private _BufferIn() As Byte

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim _EP As IPEndPoint = New IPEndPoint(IPAddress.Parse("127.0.0.1"), 21)
_FTPConn = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
_FTPConn.Connect(_EP)
ReDim _BufferIn(1024)
_FTPConn.BeginReceive(_BufferIn, 0, _BufferIn.Length, SocketFlags.None, AddressOf StreamIn, Nothing)

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("USER anonymous")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("PASS DeborggraeveR@dnb.com")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("SYST")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("PWD")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("TYPE A")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("PASV")

System.Threading.Thread.CurrentThread().Sleep(1000)
SendBuffer("LIST")

'System.Threading.Thread.CurrentThread().Sleep(1000)
'SendBuffer("DOWNLOAD")
End Sub

Private Sub StreamIn(ByVal ar As IAsyncResult)
Try
SyncLock _FTPConn
_FTPConn.EndReceive(ar)
End SyncLock

Debug.Write(System.Text.Encoding.Default.GetString(_BufferIn))
ReDim _BufferIn(1024)

SyncLock _FTPConn
_FTPConn.BeginReceive(_BufferIn, 0, _BufferIn.Length, SocketFlags.None, AddressOf StreamIn, Nothing)
End SyncLock
Catch ode As ObjectDisposedException
Debug.Write(ode)
Exit Sub
Catch se As SocketException
Debug.Write(se)
Exit Sub
Catch e As Exception
Debug.Write(e)
Exit Sub
End Try
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
SendBuffer(TextBox1.Text)
End Sub

Private Sub SendBuffer(ByVal Buffer As String)
Dim _BufferOut(1024) As Byte
Debug.Write(Buffer & Chr(10))
_BufferOut = System.Text.Encoding.Default.GetBytes(Buffer & Chr(10))
_FTPConn.Send(_BufferOut, _BufferOut.Length, SocketFlags.None)
End Sub
End Class