vb.net - los - Usar FTP para descargar cada archivo*MIENTRAS*obtener la lista de archivos
donde se guardan los archivos descargados de filezilla (2)
Necesitamos obtener aproximadamente 100 archivos muy pequeños de un servidor FTP remoto usando vb.net. Nuestra empresa no nos permitirá comprar (o instalar) bibliotecas de ftp de terceros ... por lo que nos vemos obligados a utilizar algo como FtpWebRequest. (¿O hay una mejor opción gratuita que ya forma parte de Visual Studio?)
Este método funciona, pero es MUY lento. (Supongo que debido a la constante entrada / salida).
Log in with user name and password. Get a file-list from the remote server. Log out Use that file-list to get each file separtely: Log in, get the file, log out. Log in 99 more times, get each file, log out each time.
En cambio, probablemente deberíamos estar haciendo esto, pero nunca funciona:
Log in with user name and password. ONCE. Get a list of filenames. Download each file. Log out ONCE.
Encontramos innumerables ejemplos en línea de "obtener una lista de archivos FTP" y más tarde "cómo descargar 1 archivo con FTP" ... pero nunca vemos "obtener CADA nombre de archivo y descargarlo AHORA".
Dim fwr As Net.FtpWebRequest = Net.FtpWebRequest.Create(ftpSite) fwr.Credentials = New NetworkCredential(userName, password) fwr.KeepAlive = True fwr.Method = WebRequestMethods.Ftp.ListDirectory Dim sr As IO.StreamReader = Nothing Try sr = New IO.StreamReader(fwr.GetResponse().GetResponseStream()) Do Until (sr.EndOfStream()) fileName = sr.ReadLine() fwr.Method = WebRequestMethods.Ftp.DownloadFile output = "" Dim sr2 As IO.StreamReader = Nothing Try sr2 = New IO.StreamReader(fwr.GetResponse().GetResponseStream()) output = sr2.ReadToEnd() Catch ex As Exception End Try If (Not sr2 Is Nothing) Then sr2.Close() : sr2 = Nothing Call MsgBox("Got " & fileName & LF & output) Loop Catch ex As Exception End Try If (Not sr Is Nothing) Then sr.Close() : sr = Nothing If (Not fwr Is Nothing) Then fwr = Nothing
Algo que acabo de armar, la parte importante es fwr.Proxy = Nothing, de lo contrario, intenta obtener automáticamente la configuración del proxy, lo que provoca enormes retrasos, por lo que al configurarlo en nada lo obliga a no usar uno.
Si está utilizando un proxy, obviamente, debe configurarlo a un proxy real.
Dim fwr As Net.FtpWebRequest = Net.FtpWebRequest.Create(ftpAddress)
fwr.Credentials = New NetworkCredential(userName, password)
fwr.KeepAlive = True
fwr.Method = WebRequestMethods.Ftp.ListDirectory
fwr.Proxy = Nothing
Try
Dim sr As New IO.StreamReader(fwr.GetResponse().GetResponseStream())
Dim lst = sr.ReadToEnd().Split(vbNewLine)
For Each file As String In lst
file = file.Trim() ''remove any whitespace
If file = ".." OrElse file = "." Then Continue For
Dim fwr2 As Net.FtpWebRequest = Net.FtpWebRequest.Create(ftpAddress & file)
fwr2.Credentials = fwr.Credentials
fwr2.KeepAlive = True
fwr2.Method = WebRequestMethods.Ftp.DownloadFile
fwr2.Proxy = Nothing
Dim fileSR As New IO.StreamReader(fwr2.GetResponse().GetResponseStream())
Dim fileData = fileSR.ReadToEnd()
fileSR.Close()
Next
sr.Close()
Catch ex As Exception
End Try
Sé que es un poco tarde pero espero que ayude
Eche un vistazo a mi clase de FTP, podría ser exactamente lo que necesita.
Public Class FTP
''-------------------------[BroCode]--------------------------
''----------------------------FTP-----------------------------
Private _credentials As System.Net.NetworkCredential
Sub New(ByVal _FTPUser As String, ByVal _FTPPass As String)
setCredentials(_FTPUser, _FTPPass)
End Sub
Public Sub UploadFile(ByVal _FileName As String, ByVal _UploadPath As String)
Dim _FileInfo As New System.IO.FileInfo(_FileName)
Dim _FtpWebRequest As System.Net.FtpWebRequest = CType(System.Net.FtpWebRequest.Create(New Uri(_UploadPath)), System.Net.FtpWebRequest)
_FtpWebRequest.Credentials = _credentials
_FtpWebRequest.KeepAlive = False
_FtpWebRequest.Timeout = 20000
_FtpWebRequest.Method = System.Net.WebRequestMethods.Ftp.UploadFile
_FtpWebRequest.UseBinary = True
_FtpWebRequest.ContentLength = _FileInfo.Length
Dim buffLength As Integer = 2048
Dim buff(buffLength - 1) As Byte
Dim _FileStream As System.IO.FileStream = _FileInfo.OpenRead()
Try
Dim _Stream As System.IO.Stream = _FtpWebRequest.GetRequestStream()
Dim contentLen As Integer = _FileStream.Read(buff, 0, buffLength)
Do While contentLen <> 0
_Stream.Write(buff, 0, contentLen)
contentLen = _FileStream.Read(buff, 0, buffLength)
Loop
_Stream.Close()
_Stream.Dispose()
_FileStream.Close()
_FileStream.Dispose()
Catch ex As Exception
MessageBox.Show(ex.Message, "Upload Error: ", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
End Sub
Public Sub DownloadFile(ByVal _FileName As String, ByVal _ftpDownloadPath As String)
Try
Dim _request As System.Net.FtpWebRequest = System.Net.WebRequest.Create(_ftpDownloadPath)
_request.KeepAlive = False
_request.Method = System.Net.WebRequestMethods.Ftp.DownloadFile
_request.Credentials = _credentials
Dim _response As System.Net.FtpWebResponse = _request.GetResponse()
Dim responseStream As System.IO.Stream = _response.GetResponseStream()
Dim fs As New System.IO.FileStream(_FileName, System.IO.FileMode.Create)
responseStream.CopyTo(fs)
responseStream.Close()
_response.Close()
Catch ex As Exception
MessageBox.Show(ex.Message, "Download Error: ", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
End Sub
Public Function GetDirectory(ByVal _ftpPath As String) As List(Of String)
Dim ret As New List(Of String)
Try
Dim _request As System.Net.FtpWebRequest = System.Net.WebRequest.Create(_ftpPath)
_request.KeepAlive = False
_request.Method = System.Net.WebRequestMethods.Ftp.ListDirectoryDetails
_request.Credentials = _credentials
Dim _response As System.Net.FtpWebResponse = _request.GetResponse()
Dim responseStream As System.IO.Stream = _response.GetResponseStream()
Dim _reader As System.IO.StreamReader = New System.IO.StreamReader(responseStream)
Dim FileData As String = _reader.ReadToEnd
Dim Lines() As String = FileData.Split(New String() {Environment.NewLine}, StringSplitOptions.RemoveEmptyEntries)
For Each l As String In Lines
ret.Add(l)
Next
_reader.Close()
_response.Close()
Catch ex As Exception
MessageBox.Show(ex.Message, "Directory Fetch Error: ", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try
Return ret
End Function
Private Sub setCredentials(ByVal _FTPUser As String, ByVal _FTPPass As String)
_credentials = New System.Net.NetworkCredential(_FTPUser, _FTPPass)
End Sub
End Class
Para inicializar:
Dim ftp As New FORM.FTP("username", "password")
ftp.UploadFile("c:/file.jpeg", "ftp://domain/file.jpeg")
ftp.DownloadFile("c:/file.jpeg", "ftp://ftp://domain/file.jpeg")
Dim directory As List(Of String) = ftp.GetDirectory("ftp://ftp.domain.net/")
ListBox1.Items.Clear()
For Each item As String In directory
ListBox1.Items.Add(item)
Next