Imports System
Imports System.Net
Imports System.IO
Imports System.Text
Imports System.Net.Sockets
Public Class FTPAccess
#Region "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
Public m_bLoggedIn As Boolean
Private m_sMes, m_sReply As String
'Set the size of the packet that is used to read and to write data to the FTP server
'to the following specified size.
Public Const BLOCK_SIZE = 512
Private m_aBuffer(BLOCK_SIZE) As Byte
Private ASCII As Encoding = Encoding.ASCII
Public flag_bool As Boolean
'General variable declaration
Private m_sMessageString As String
#End Region
#Region "Class Constructors"
' Main class constructor
Public Sub New()
m_sRemoteHost = "microsoft"
m_sRemotePath = "."
m_sRemoteUser = "anonymous"
m_sRemotePassword = ""
m_sMessageString = ""
m_iRemotePort = 21
m_bLoggedIn = False
End Sub
' Parameterized constructor
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 = 21
m_bLoggedIn = False
End Sub
#End Region
#Region "FTP连接相关设置 "
'Set or Get the name of the FTP server that you want to connect.
Public Property RemoteHostFTPServer() As String
'Get the name of the FTP server.
Get
Return m_sRemoteHost
End Get
'Set the name of the FTP server.
Set(ByVal Value As String)
m_sRemoteHost = Value
End Set
End Property
'Set or Get the
Public Property RemotePort() As Int32
'Get the
Get
Return m_iRemotePort
End Get
'Set the
Set(ByVal Value As Int32)
m_iRemotePort = Value
End Set
End Property
'Set or Get the remote path of the FTP server that you want to connect.
Public Property RemotePath() As String
'Get the remote path.
Get
Return m_sRemotePath
End Get
'Set the remote path.
Set(ByVal Value As String)
m_sRemotePath = Value
End Set
End Property
'Set or Get the remote password of the FTP server that you want to connect.
Public Property RemotePassword() As String
Get
Return m_sRemotePassword
End Get
Set(ByVal Value As String)
m_sRemotePassword = Value
End Set
End Property
'Set or Get the remote user of the FTP server that you want to connect.
Public Property RemoteUser() As String
Get
Return m_sRemoteUser
End Get
Set(ByVal Value As String)
m_sRemoteUser = Value
End Set
End Property
'Set the class MessageString.
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"
#Region "获取FTP服务器中指定目录的所有文件名"
'Return a list of files in a string() array from the file system.
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
Dim i As Integer = 0
m_sMes = ""
'Check if you are logged on to the FTP server.
If (Not (m_bLoggedIn)) Then
Login()
End If
cSocket = CreateDataSocket()
'Send an FTP command,
SendCommand("NLST " & sMask)
If (Not (m_iRetValue = 150 Or m_iRetValue = 125)) Then
'output.Close()
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)
For i = 0 To mess.Length - 1
If mess(i) <> "" Then
mess(i) = Microsoft.VisualBasic.Left(mess(i), Len(mess(i)) - 1)
End If
Next i
cSocket.Close()
ReadReply()
If (m_iRetValue <> 226) Then
MessageString = m_sReply
Throw New IOException(m_sReply.Substring(4))
End If
Return mess
End Function
#End Region
#Region "取得文件大小"
' 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
'Send an FTP command.
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
#End Region
#Region "FTP登录联结Log on"
'Log on to 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("Cannot 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
'Send an FTP command to send a user logon ID to the server.
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
'Send an FTP command to send a user logon password to the server.
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
'Call the ChangeDirectory user-defined function to change the folder to the
'remote FTP folder that is mapped.
ChangeDirectory(m_sRemotePath)
'Return the final result.
Return m_bLoggedIn
End Function
#End Region
#Region "BinaryMode"
'If the value of mode is true, set the binary mode for downloads. Otherwise, set ASCII mode.
Public Sub SetBinaryMode(ByVal bMode As Boolean)
If (bMode) Then
'Send the FTP command to set the binary mode.
'(TYPE is an FTP command that is used to specify representation type.)
SendCommand("TYPE I")
Else
'Send the FTP command to set ASCII mode.
'(TYPE is a FTP command that is used to specify representation type.)
SendCommand("TYPE A")
End If
If (m_iRetValue <> 200) Then
MessageString = m_sReply
Throw New IOException(m_sReply.Substring(4))
End If
End Sub
#End Region
#Region "FTP文件下载"
' Download a file to the local folder of the assembly, and keep the same file name.
Public Sub DownloadFile(ByVal sFileName As String)
DownloadFile(sFileName, "", False)
End Sub
' Download a remote file to the local folder of the assembly, and keep the same file name.
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. You must include a path.
'The local file name will be created or will be 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 and include a path. Then, set the
' resume flag. The local file name will be created or will be 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
'Send an FTP command to restart.
SendCommand("REST " & offset)
If (m_iRetValue <> 350) Then
offset = 0
End If
End If
If (offset > 0) Then
npos = output.Seek(offset, SeekOrigin.Begin)
End If
End If
'Send an FTP command to retrieve a file.
SendCommand("RETR " & sFileName)
If (Not (m_iRetValue = 150 Or m_iRetValue = 125)) Then
output.Close()
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
#End Region
#Region "FTP文件上传"
' This is a function that is used to upload a file from your local hard disk to your FTP site.
Public Sub UploadFile(ByVal sFileName As String)
UploadFile(sFileName, False)
End Sub
' This is a function that is used to upload a file from your local hard disk to your FTP site
' and then 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
Try
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
'The remote server may not support resuming.
offset = 0
End If
End If
'Send an FTP command to store a file.
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 the input stream to read the 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)
input.Close()
Else
bFileNotFound = True
End If
If (cSocket.Connected) Then
cSocket.Close()
End If
'Check the return value if the file was not found.
If (bFileNotFound) Then
MessageString = m_sReply
Throw New IOException("The file: " & sFileName & " was not found." & _
" Cannot 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
Finally
If Not IsNothing(input) Then
input.Close()
End If
'姰旛偟偰偄側偄僼傽僀儖傪嶍彍偡傞
If (cSocket.Connected) Then
cSocket.Close()
If (sFileName <> "") And (sFileName.IndexOf("\") <> -1) Then
Dim index As String = sFileName.LastIndexOf("\")
Dim TempFileName As String
TempFileName = sFileName.Substring(index + 1, sFileName.Length - index - 1)
DeleteFile(TempFileName)
End If
End If
End Try
End Sub
#End Region
#Region "FTP上的文件删除"
' 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
'Send an FTP command to delete a file.
SendCommand("DELE " & sFileName)
If (m_iRetValue <> 250) Then
bResult = False
MessageString = m_sReply
End If
' Return the final result.
Return bResult
End Function
#End Region
#Region "FTP上的文件重命名"
' 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
'Send an FTP command to rename a file.
SendCommand("RNFR " & sOldFileName)
If (m_iRetValue <> 350) Then
MessageString = m_sReply
Throw New IOException(m_sReply.Substring(4))
End If
'Send an FTP command to rename a file to a file name.
'It will overwrite if newFileName exists.
SendCommand("RNTO " & sNewFileName)
If (m_iRetValue <> 250) Then
MessageString = m_sReply
Throw New IOException(m_sReply.Substring(4))
End If
' Return the final result.
Return bResult
End Function
#End Region
#Region "FTP文件夹操作"
'This is a function that is used to create a folder 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
'Send an FTP command to make a folder on the FTP server.
SendCommand("MKD " & sDirName)
If (m_iRetValue <> 257) Then
bResult = False
MessageString = m_sReply
End If
' Return the final result.
Return bResult
End Function
' This is a function that is used to delete a folder on the remote FTP server.
Public Function RemoveDirectory(ByVal sDirName As String) As Boolean
Dim bResult As Boolean
bResult = True
'Check if you are logged on to the FTP server.
If (Not (m_bLoggedIn)) Then
Login()
End If
'Send an FTP command to remove a folder on the FTP server.
SendCommand("RMD " & sDirName)
If (m_iRetValue <> 250) Then
bResult = False
MessageString = m_sReply
End If
' Return the final result.
Return bResult
End Function
'This is a function that is used to change the current working folder on the remote FTP server.
Public Function ChangeDirectory(ByVal sDirName As String) As Boolean
Dim bResult As Boolean
bResult = True
'Check if you are in the root directory.
If (sDirName.Equals(".")) Then
Exit Function
End If
'Check if you are logged on to the FTP server.
If (Not (m_bLoggedIn)) Then
Login()
End If
'Send an FTP command to change the folder on the FTP server.
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
#End Region
#Region "FTP_QUIT"
' Close the FTP connection of the remote server.
Public Sub QUIT()
If (Not (m_objClientSocket Is Nothing)) Then
'Send an FTP command to end an FTP server system.
SendCommand("QUIT")
End If
Cleanup()
End Sub
#End Region
#Region "关闭FTP连接"
' Close the FTP connection of the remote server.
Public Sub CloseConnection()
If (Not (m_objClientSocket Is Nothing)) Then
'Send an FTP command to close an FTP server system.
SendCommand("Close")
End If
Cleanup()
End Sub
#End Region
#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 FTP 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
' This is a function that is used to send a command to the FTP server that you are connected to.
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
'Send an FTP command to use a passive data connection.
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)
' Make this call in Visual Basic .NET 2002. You want to
' bitshift the number by 8 bits. Therefore, in Visual Basic .NET 2002, you must
' multiply the number by 2 to the power of 8.
'port = parts(4) * (2 ^ 8)
' Make this call and then comment out the previous line for Visual Basic .NET 2003.
port = parts(4) << 8
' Determine the data port number.
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("Cannot connect to remote server")
'If you cannot connect to the FTP
'server that is specified, make the boolean variable false.
flag_bool = False
End Try
'If you can connect to the FTP server that is specified, make the boolean variable true.
flag_bool = True
Return s
End Function
#End Region
End Class
