[Visual Basic] FTP Klasse

Imports System
Imports System.Net
Imports System.IO
Imports System.Text
Imports System.Net.Sockets

' Main FTP Class.
Public Class clsFTP

#Region "Main Class Variable Declarations"
 Private m_sRemoteHost, m_sRemotePath, m_sRemoteUser As String
 Private m_sRemotePassword, m_sMess As String
 Private m_iRemotePort, m_iBytes As Int32
 Private m_objClientSocket As Socket

 Private m_iRetValue As Int32
 Private m_bLoggedIn As Boolean ' Change to loggedIn
 Private m_sMes, m_sReply As String


 Public Const BLOCK_SIZE = 512
 Private m_aBuffer(BLOCK_SIZE) As Byte
 Private ASCII As Encoding = Encoding.ASCII

 
 Private m_sMessageString As String
#End Region

#Region "Class Constructors"
 
 Public Sub New()
 m_sRemoteHost = "microsoft"
 m_sRemotePath = "."
 m_sRemoteUser = "anonymous"
 m_sRemotePassword = ""
 m_sMessageString = ""
 m_iRemotePort = 21
 m_bLoggedIn = False
 End Sub

 Public Sub New(ByVal sRemoteHost As String, _
 ByVal sRemotePath As String, _
 ByVal sRemoteUser As String, _
 ByVal sRemotePassword As String, _
 ByVal iRemotePort As Int32)
 m_sRemoteHost = sRemoteHost
 m_sRemotePath = sRemotePath
 m_sRemoteUser = sRemoteUser
 m_sRemotePassword = sRemotePassword
 m_sMessageString = ""
 m_iRemotePort = iRemotePort
 m_bLoggedIn = False
 End Sub
#End Region

#Region "Public Properties"
 
 Public Property RemoteHost() As String
 Get
 Return m_sRemoteHost
 End Get
 Set(ByVal Value As String)
 m_sRemoteHost = Value
 End Set
 End Property

 
 Public Property RemotePort() As Int32
 Get
 Return m_iRemotePort
 End Get
 Set(ByVal Value As Int32)
 m_iRemotePort = Value
 End Set
 End Property


 Public Property RemotePath() As String
 Get
 Return m_sRemotePath
 End Get
 Set(ByVal Value As String)
 m_sRemotePath = Value
 End Set
 End Property

 
 Public Property RemotePassword() As String
 Get
 Return m_sRemotePassword
 End Get
 Set(ByVal Value As String)
 m_sRemotePassword = Value
 End Set
 End Property

 
 Public Property RemoteUser() As String
 Get
 Return m_sRemoteUser
 End Get
 Set(ByVal Value As String)
 m_sRemoteUser = Value
 End Set
 End Property

 
 Public Property MessageString() As String
 Get
 Return m_sMessageString
 End Get
 Set(ByVal Value As String)
 m_sMessageString = Value
 End Set
 End Property

#End Region

#Region "Public Subs and Functions"
 
 Public Function GetFileList(ByVal sMask As String) As String()
 Dim cSocket As Socket
 Dim bytes As Int32
 Dim seperator As Char = ControlChars.Lf
 Dim mess() As String

 m_sMes = ""
 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 cSocket = CreateDataSocket()
 SendCommand("NLST " & sMask)

 If (Not (m_iRetValue = 150 Or m_iRetValue = 125)) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 m_sMes = ""
 Do While (True)
 m_aBuffer.Clear(m_aBuffer, 0, m_aBuffer.Length)
 bytes = cSocket.Receive(m_aBuffer, m_aBuffer.Length, 0)
 m_sMes += ASCII.GetString(m_aBuffer, 0, bytes)

 If (bytes < m_aBuffer.Length) Then
 Exit Do
 End If
 Loop

 mess = m_sMes.Split(seperator)
 cSocket.Close()
 ReadReply()

 If (m_iRetValue <> 226) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 Return mess
 End Function

 '
 ' Get the size of the file on the FTP Server.
 Public Function GetFileSize(ByVal sFileName As String) As Long
 Dim size As Long

 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("SIZE " & sFileName)
 size = 0

 If (m_iRetValue = 213) Then
 size = Int64.Parse(m_sReply.Substring(4))
 Else
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 Return size
 End Function

 '
 ' Log into the FTP Server.
 Public Function Login() As Boolean
 m_objClientSocket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
 Dim ep As New IPEndPoint(Dns.Resolve(m_sRemoteHost).AddressList(0), m_iRemotePort)

 Try
 m_objClientSocket.Connect(ep)
 Catch ex As Exception
 MessageString = m_sReply
 Throw New IOException("Couldn't connect to remote server")
 End Try

 ReadReply()
 If (m_iRetValue <> 220) Then
 CloseConnection()
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 SendCommand("USER " & m_sRemoteUser)
 If (Not (m_iRetValue = 331 Or m_iRetValue = 230)) Then
 Cleanup()
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 If (m_iRetValue <> 230) Then
 SendCommand("PASS " & m_sRemotePassword)
 If (Not (m_iRetValue = 230 Or m_iRetValue = 202)) Then
 Cleanup()
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If
 End If

 m_bLoggedIn = True
 ChangeDirectory(m_sRemotePath)

 ' Return the end result.
 Return m_bLoggedIn
 End Function

 '
 ' If the value of mode is true, set binary mode for 
 ' downloads.
 ' Else, set Ascii mode.
 Public Sub SetBinaryMode(ByVal bMode As Boolean)

 If (bMode) Then
 SendCommand("TYPE I")
 Else
 SendCommand("TYPE A")
 End If

 If (m_iRetValue <> 200) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If
 End Sub

 '
 ' Download a file to the Assembly's local directory,
 ' keeping the same file name.
 Public Sub DownloadFile(ByVal sFileName As String)
 DownloadFile(sFileName, "", False)
 End Sub

 '
 ' Download a remote file to the Assembly's local 
 ' directory, keeping the same file name, and set 
 ' the resume flag.
 Public Sub DownloadFile(ByVal sFileName As String, _
 ByVal bResume As Boolean)
 DownloadFile(sFileName, "", bResume)
 End Sub

 '
 ' Download a remote file to a local file name which can 
 ' include a path. The local file name will be created or 
 ' overwritten, but the path must exist.
 Public Sub DownloadFile(ByVal sFileName As String, _
 ByVal sLocalFileName As String)
 DownloadFile(sFileName, sLocalFileName, False)
 End Sub

 '
 ' Download a remote file to a local file name which can 
 ' include a path, and set the resume flag. The local file 
 ' name will be created or overwritten, but the path must 
 ' exist.
 Public Sub DownloadFile(ByVal sFileName As String, _
 ByVal sLocalFileName As String, _
 ByVal bResume As Boolean)
 Dim st As Stream
 Dim output As FileStream
 Dim cSocket As Socket
 Dim offset, npos As Long

 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SetBinaryMode(True)

 If (sLocalFileName.Equals("")) Then
 sLocalFileName = sFileName
 End If

 If (Not (File.Exists(sLocalFileName))) Then
 st = File.Create(sLocalFileName)
 st.Close()
 End If

 output = New FileStream(sLocalFileName, FileMode.Open)
 cSocket = CreateDataSocket()
 offset = 0

 If (bResume) Then
 offset = output.Length

 If (offset > 0) Then
 SendCommand("REST " & offset)
 If (m_iRetValue <> 350) Then
 'throw new IOException(reply.Substring(4));
 'Some servers may not support resuming.
 offset = 0
 End If
 End If

 If (offset > 0) Then
 npos = output.Seek(offset, SeekOrigin.Begin)
 End If
 End If

 SendCommand("RETR " & sFileName)

 If (Not (m_iRetValue = 150 Or m_iRetValue = 125)) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 Do While (True)
 m_aBuffer.Clear(m_aBuffer, 0, m_aBuffer.Length)
 m_iBytes = cSocket.Receive(m_aBuffer, m_aBuffer.Length, 0)
 output.Write(m_aBuffer, 0, m_iBytes)

 If (m_iBytes <= 0) Then
 Exit Do
 End If
 Loop

 output.Close()
 If (cSocket.Connected) Then
 cSocket.Close()
 End If

 ReadReply()
 If (Not (m_iRetValue = 226 Or m_iRetValue = 250)) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 End Sub

 '
 ' Upload a file.
 Public Sub UploadFile(ByVal sFileName As String)
 UploadFile(sFileName, False)
 End Sub

 '
 ' Upload a file and set the resume flag.
 Public Sub UploadFile(ByVal sFileName As String, _
 ByVal bResume As Boolean)
 Dim cSocket As Socket
 Dim offset As Long
 Dim input As FileStream
 Dim bFileNotFound As Boolean

 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 cSocket = CreateDataSocket()
 offset = 0

 If (bResume) Then
 Try
 SetBinaryMode(True)
 offset = GetFileSize(sFileName)
 Catch ex As Exception
 offset = 0
 End Try
 End If

 If (offset > 0) Then
 SendCommand("REST " & offset)
 If (m_iRetValue <> 350) Then
 'throw new IOException(reply.Substring(4));
 'Remote server may not support resuming.
 offset = 0
 End If
 End If

 SendCommand("STOR " & Path.GetFileName(sFileName))
 If (Not (m_iRetValue = 125 Or m_iRetValue = 150)) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 ' Check to see if the file exists before the upload.
 bFileNotFound = False
 If (File.Exists(sFileName)) Then
 ' Open input stream to read source file
 input = New FileStream(sFileName, FileMode.Open)
 If (offset <> 0) Then
 input.Seek(offset, SeekOrigin.Begin)
 End If

 ' Upload the file 
 m_iBytes = input.Read(m_aBuffer, 0, m_aBuffer.Length)
 Do While (m_iBytes > 0)
 cSocket.Send(m_aBuffer, m_iBytes, 0)
 m_iBytes = input.Read(m_aBuffer, 0, m_aBuffer.Length)
 Loop
 input.Close()
 Else
 bFileNotFound = True
 End If

 If (cSocket.Connected) Then
 cSocket.Close()
 End If

 ' No point in reading the return value if the file was
 ' not found.
 If (bFileNotFound) Then
 MessageString = m_sReply
 Throw New IOException("The file: " & sFileName & " was not found. Can not upload the file to the FTP Site.")
 End If

 ReadReply()
 If (Not (m_iRetValue = 226 Or m_iRetValue = 250)) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If
 End Sub

 '
 ' Delete a file from the remote FTP server.
 Public Function DeleteFile(ByVal sFileName As String) As Boolean
 Dim bResult As Boolean

 bResult = True
 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("DELE " & sFileName)
 If (m_iRetValue <> 250) Then
 bResult = False
 MessageString = m_sReply
 End If

 ' Return the final result.
 Return bResult
 End Function

 '
 ' Rename a file on the remote FTP server.
 Public Function RenameFile(ByVal sOldFileName As String, _
 ByVal sNewFileName As String) As Boolean
 Dim bResult As Boolean

 bResult = True
 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("RNFR " & sOldFileName)
 If (m_iRetValue <> 350) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 ' known problem
 ' rnto will not take care of existing file.
 ' i.e. It will overwrite if newFileName exist
 SendCommand("RNTO " & sNewFileName)
 If (m_iRetValue <> 250) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 Return bResult
 End Function

 '
 ' Create a directory on the remote FTP server.
 Public Function CreateDirectory(ByVal sDirName As String) As Boolean
 Dim bResult As Boolean

 bResult = True
 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("MKD " & sDirName)
 If (m_iRetValue <> 257) Then
 bResult = False
 MessageString = m_sReply
 End If

 ' Return the final result.
 Return bResult
 End Function

 '
 ' Delete a directory on the remote FTP server.
 Public Function RemoveDirectory(ByVal sDirName As String) As Boolean
 Dim bResult As Boolean

 bResult = True
 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("RMD " & sDirName)
 If (m_iRetValue <> 250) Then
 bResult = False
 MessageString = m_sReply
 End If

 ' Return the final result.
 Return bResult
 End Function

 '
 ' Change the current working directory on the remote FTP 
 ' server.
 Public Function ChangeDirectory(ByVal sDirName As String) As Boolean
 Dim bResult As Boolean

 bResult = True
 If (sDirName.Equals(".")) Then
 Exit Function
 End If

 If (Not (m_bLoggedIn)) Then
 Login()
 End If

 SendCommand("CWD " & sDirName)
 If (m_iRetValue <> 250) Then
 bResult = False
 MessageString = m_sReply
 End If

 Me.m_sRemotePath = sDirName

 ' Return the final result.
 Return bResult
 End Function

 '
 ' Close the FTP connection.
 Public Sub CloseConnection()
 If (Not (m_objClientSocket Is Nothing)) Then
 SendCommand("QUIT")
 End If

 Cleanup()
 End Sub

#End Region

#Region "Private Subs and Functions"
 '
 ' Read the reply from the FTP Server
 Private Sub ReadReply()
 m_sMes = ""
 m_sReply = ReadLine()
 m_iRetValue = Int32.Parse(m_sReply.Substring(0, 3))
 End Sub

 '
 ' Clean up some variables.
 Private Sub Cleanup()
 If Not (m_objClientSocket Is Nothing) Then
 m_objClientSocket.Close()
 m_objClientSocket = Nothing
 End If

 m_bLoggedIn = False
 End Sub

 '
 ' Read a line from the server.
 Private Function ReadLine(Optional ByVal bClearMes As Boolean = False) As String
 Dim seperator As Char = ControlChars.Lf
 Dim mess() As String

 If (bClearMes) Then
 m_sMes = ""
 End If
 Do While (True)
 m_aBuffer.Clear(m_aBuffer, 0, BLOCK_SIZE)
 m_iBytes = m_objClientSocket.Receive(m_aBuffer, m_aBuffer.Length, 0)
 m_sMes += ASCII.GetString(m_aBuffer, 0, m_iBytes)
 If (m_iBytes < m_aBuffer.Length) Then
 Exit Do
 End If
 Loop

 mess = m_sMes.Split(seperator)
 If (m_sMes.Length > 2) Then
 m_sMes = mess(mess.Length - 2)
 Else
 m_sMes = mess(0)
 End If

 If (Not (m_sMes.Substring(3, 1).Equals(" "))) Then
 Return ReadLine(True)
 End If

 Return m_sMes
 End Function

 '
 ' Send a command to the FTP Server.
 Private Sub SendCommand(ByVal sCommand As String)
 sCommand = sCommand & ControlChars.CrLf
 Dim cmdbytes As Byte() = ASCII.GetBytes(sCommand)

 m_objClientSocket.Send(cmdbytes, cmdbytes.Length, 0)
 ReadReply()
 End Sub

 '
 ' Create a Data socket.
 Private Function CreateDataSocket() As Socket
 Dim index1, index2, len As Int32
 Dim partCount, i, port As Int32
 Dim ipData, buf, ipAddress As String
 Dim parts(6) As Int32
 Dim ch As Char
 Dim s As Socket
 Dim ep As IPEndPoint

 SendCommand("PASV")
 If (m_iRetValue <> 227) Then
 MessageString = m_sReply
 Throw New IOException(m_sReply.Substring(4))
 End If

 index1 = m_sReply.IndexOf("(")
 index2 = m_sReply.IndexOf(")")
 ipData = m_sReply.Substring(index1 + 1, index2 - index1 - 1)

 len = ipData.Length
 partCount = 0
 buf = ""

 For i = 0 To ((len - 1) And partCount <= 6)
 ch = Char.Parse(ipData.Substring(i, 1))
 If (Char.IsDigit(ch)) Then
 buf += ch
 ElseIf (ch <> ",") Then
 MessageString = m_sReply
 Throw New IOException("Malformed PASV reply: " & m_sReply)
 End If

 If ((ch = ",") Or (i + 1 = len)) Then
 Try
 parts(partCount) = Int32.Parse(buf)
 partCount += 1
 buf = ""
 Catch ex As Exception
 MessageString = m_sReply
 Throw New IOException("Malformed PASV reply: " & m_sReply)
 End Try
 End If
 Next

 ipAddress = parts(0) & "." & parts(1) & "." & parts(2) & "." & parts(3)

 port = parts(4) * (2 ^ 8)

 
 

 port = port + parts(5)

 s = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
 ep = New IPEndPoint(Dns.Resolve(ipAddress).AddressList(0), port)

 Try
 s.Connect(ep)
 Catch ex As Exception
 MessageString = m_sReply
 Throw New IOException("Can't connect to remote server")
 End Try

 Return s
 End Function
#End Region
End Class