How to use FTP with VB.NET

0

Posted on : 13-01-2011 | By : ocx | In : Develop
1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
Loading ... Loading ...

Please note: this how-to article refer to software developers and software authors.

This demonstrate will show you how to add FTP functionality to your program using the FTP Client ActiveX.

Requirements:

This sample using VB.NET. The VB6 sample existed under the installation program of the component.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
 
Private Sub chkAnonym_CheckStateChanged(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles chkAnonym.CheckStateChanged
    If chkAnonym.CheckState Then
        txtUserName.Text = "anonymous"
        txtPassword.PasswordChar = CChar("")
        txtPassword.Text = "guest@unknow.com"
 
    Else
        txtUserName.Text = ""
        txtPassword.PasswordChar = CChar("*")
        txtPassword.Text = ""
    End If
End Sub
 
Private Sub cmdViewFile_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdViewFile.Click
 
    'Download the file then open the file.
    
End Sub
 
Private Sub frmMain_Load(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles MyBase.Load
 
    'Init the control:
    'Must be call before using any
    'functionality of the control.
    'sKey = Your registration key.
    'On trial mode use the "Trial Mode."
    cFtp1.Init ("Trial Mode.")
 
End Sub
 
Private Sub frmMain_Closed(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles MyBase.Closed
 
    'Release the control
    'from the memory:
    cFtp1.DeInit()
 
End Sub
 
Private Sub cmdConnect_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdConnect.Click
 
    'Connect to the FTP server
    
    On Error GoTo ErrConnect
 
    'Clear the 'ftp://' string from the address (if any)
    If LCase(VB.Left(txtServer.Text, Len("ftp://"))) = "ftp://" Then
        txtServer.Text = Mid(txtServer.Text, Len("ftp://") + 1)
    End If
 
    'Clear the 'http://' string from the address (if any)
    If LCase(VB.Left(txtServer.Text, Len("http://"))) = "http://" Then
        txtServer.Text = Mid(txtServer.Text, Len("http://") + 1)
    End If
 
    'Set the FTP server properties:
    cFtp1.FtpRemotePort = Val(txtRemotePort.Text)
    cFtp1.FtpServer = txtServer.Text
    cFtp1.FtpUserName = txtUserName.Text
    cFtp1.FtpPassword = txtPassword.Text
    cFtp1.FtpPassiveMode = CBool(chkPassive.CheckState)
    cFtp1.Timeout = Val(txtTimeOut.Text)
 
    'Connect to the server:
    cFtp1.Connect()
 
    'Get the main path
    cFtp1.PathDir ("/")
 
    Exit Sub
 
    'On Error
ErrConnect:
    MsgBox (Err.Description) 'Or cFtp1.GetFtpErrorDescription(Err.Number)
    
End Sub
 
Private Sub cmdDeleteDir_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdDeleteDir.Click
 
    'Delete a directory from the FTP server
    
    Dim strDirName As String
    strDirName = cmbRemote.Text & "/" & Trim(VB6.GetItemString(lstRemote, lstRemote.SelectedIndex))
 
    'Check if this is a directory
    If cFtp1.RemoveDirectory(strDirName) = True Then
 
        'Success, reload the directory
        ReloadDir()
 
    Else
 
        'An error: display a message
        MsgBox("Can't remove directory from the FTP server." & vbCrLf & vbCrLf & "FTP server: " & cFtp1.GetLastServerResponse, MsgBoxStyle.Information, "Can't remove directory from the FTP server.")
    End If
 
End Sub
 
Private Sub cmdDeleteFile_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdDeleteFile.Click
 
    'Delete a file from the FTP server
    
    Dim strFileName As String
    strFileName = cmbRemote.Text & "/" & Trim(VB6.GetItemString(lstRemote, lstRemote.SelectedIndex))
 
    'Check if the item is a file
    If cFtp1.DeleteFile(strFileName) = True Then
 
        'Success, Reload the directory
        ReloadDir()
 
    Else
 
        'An error: display a message
        MsgBox("Can't delete file." & vbCrLf & vbCrLf & "FTP server: " & cFtp1.GetLastServerResponse, MsgBoxStyle.Information, "Can't delete file from the FTP server")
    End If
End Sub
 
Private Sub cmdDisconnect_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdDisconnect.Click
 
    'Disconnect the FTP server
    
    cFtp1.Disconnect()
 
End Sub
 
Private Sub cmdNewDir_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdNewDir.Click
 
    'Create a new directory in the FTP server under
    'the the current directory
    
    Dim strDirName As String
 
    strDirName = InputBox("Please enter a directory name.", "Create new directory")
    If Len(strDirName) > 0 Then
        If cFtp1.CreateDirectory(strDirName) = True Then
 
            'Success, Reload the directory
            ReloadDir()
 
        Else
 
            'An error: display a message
            MsgBox("Can't create new directory on the FTP server." & vbCrLf & vbCrLf & "FTP server: " & cFtp1.GetLastServerResponse, MsgBoxStyle.Information, "Can't create directory")
        End If
    End If
 
End Sub
 
Private Sub cmdRefresh_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdRefresh.Click
 
    'Display the files
    ReloadDir()
 
End Sub
 
Private Sub cmdRename_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdRename.Click
 
    'Rename file/directory
    
    Dim strName As String
    Dim strNewName As String
    Dim intAnswer As Short
 
    On Error GoTo ErrCmdRename
 
    'Get the name to rename
    strName = VB6.GetItemString(lstRemote, lstRemote.SelectedIndex)
 
    'Get the new name
    strNewName = InputBox("Please enter new name for " & strName, "Rename")
 
    If Len(strNewName) > 0 Then
 
        'Ask the user
        intAnswer = MsgBox("Rename " & strName & " to " & strNewName & "?", MsgBoxStyle.YesNo + MsgBoxStyle.Question, "Rename File")
 
 
        If intAnswer = MsgBoxResult.Yes Then
 
            'Rename
            If cFtp1.Rename(strName, strNewName) = True Then
                ReloadDir()
            Else
 
                'An error apears
                MsgBox("Can't rename the file." & vbCrLf & vbCrLf & "Server response: " & cFtp1.GetLastServerResponse,  , "Can't rename file")
            End If
        End If
 
    End If
 
    Exit Sub
 
ErrCmdRename:
    If Err.Number = 91 Then
        MsgBox("Please select a file to rename.", MsgBoxStyle.Information, "Rename File")
    Else
        MsgBox("Error:" & vbCrLf & "#" & Err.Number & ": " & Err.Description, MsgBoxStyle.Information, "Rename File")
    End If
 
End Sub
 
 
Private Sub cmdUploadFile_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdUploadFile.Click
 
    'Upload a file to the FTP server
    
    Dim sFile As String
    Dim strFileName As String
    Dim iTransMode As FTP_CLIENT_ACTIVEX.FtpTransferMode
    Dim lStartPoint As Integer
    Dim lFileSize As Integer
 
    With CommonDialog1
 
        'Select the file to upload
        .DialogTitle = "Select file to upload"
        .CancelError = True
        .Filter = "All Files (*.*)|*.*"
 
        'Open the dialog
        .ShowOpen()
 
        If Err.Number = 0 Then
 
            If Len(.FileName) = 0 Then
                Exit Sub
            End If
 
            'Get the file to upload
            sFile = Mid(.FileName, InStrRev(.FileName, "\") + 1)
 
            'File type upload mode
            If Option1(0).Checked = True Then
                iTransMode = FTP_CLIENT_ACTIVEX.FtpTransferMode.FTP_ASCII_MODE
            Else
                iTransMode = FTP_CLIENT_ACTIVEX.FtpTransferMode.FTP_IMAGE_MODE
            End If
 
            'Upload the file
            If cFtp1.UploadFile(.FileName, sFile, iTransMode, lStartPoint) = True Then
                ReloadDir()
            Else
                'Error
                MsgBox("Can't upload file." & vbCrLf & vbCrLf & "Server response: " & cFtp1.GetLastServerResponse,  , "Can't upload file")
            End If
 
            'The operation has done.
            MsgBox ("DONE.")
 
        End If
    End With
 
End Sub
 
Public Function ReloadDir() As Object
 
    'Reload directory:
    
    lstRemote.Items.Clear()
    cFtp1.PathDir (cmbRemote.Text)
 
End Function
 
Private Sub cmdDownload_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles cmdDownload.Click
 
    'Download a file from the FTP server:
    
    On Error Resume Next
 
    Dim sFileSize As String
    Dim lStartPoint As Integer
    Dim bForceDownload As Boolean
    Dim vTransferMode As FTP_CLIENT_ACTIVEX.FtpTransferMode
    Dim sFile As String
    Dim lFileSize As Integer
    Dim intRetVal As Short
 
    'Display a Save As dialog
    CommonDialog1.DialogTitle = "Save as..."
    CommonDialog1.Filter = "All Files (*.*)|*.*"
    CommonDialog1.CancelError = True
    CommonDialog1.FileName = VB6.GetItemString(lstRemote, lstRemote.SelectedIndex)
    CommonDialog1.ShowSave()
 
    If Err.Number = 0 Then
 
        If Len(CommonDialog1.FileName) = 0 Then
            Exit Function
        End If
 
        'Get the info
        sFile = VB6.GetItemString(lstRemote, lstRemote.SelectedIndex)
        lFileSize = CInt(VB6.GetItemString(lstRemote, lstRemote.SelectedIndex))
 
        'File type mode
        If CBool(Option1(0).Checked) Then
            vTransferMode = FTP_CLIENT_ACTIVEX.FtpTransferMode.FTP_ASCII_MODE
        Else
            vTransferMode = FTP_CLIENT_ACTIVEX.FtpTransferMode.FTP_IMAGE_MODE
        End If
 
TryAgain:
        'Download the file
        If Not cFtp1.DownloadFile(sFile, CommonDialog1.FileName, vTransferMode, lStartPoint) Then
 
            'Check if there is an error: BadState
            If cFtp1.FtpGetLastError = FTP_CLIENT_ACTIVEX.FtpError.ERROR_FTP_WINSOCK_BadState Then
 
                'The connection is broken
                intRetVal = MsgBox("The connection to the FTP server is broken. Establish the connect again?", MsgBoxStyle.Question + MsgBoxStyle.YesNo)
                If intRetVal = MsgBoxResult.Yes Then
 
                    'So try again
                    If cFtp1.Connect Then
                        If cFtp1.SetCurrentDirectory(cmbRemote.Text & "/" & Trim(VB6.GetItemString(lstRemote, lstRemote.SelectedIndex))) Then
                            GoTo TryAgain
                        End If
                    Else
 
                        'Error: The connection cannot be established.
                        MsgBox("The connection to the FTP server cannot established.", MsgBoxStyle.Exclamation)
 
                    End If
                Else
                    'Call ResetProgress
                End If
 
                'Check if there is an error: Timeout over
            ElseIf cFtp1.FtpGetLastError = FTP_CLIENT_ACTIVEX.FtpError.ERROR_FTP_USER_TIMEOUT Then
 
                'The server is not responding
                intRetVal = MsgBox("The FTP server is not responding. Try again?", MsgBoxStyle.YesNo + MsgBoxStyle.Question)
 
                'Try again:
                If intRetVal = MsgBoxResult.Yes Then
                    GoTo TryAgain
                Else
                    'Call ResetProgress
                End If
 
            Else
 
                'Error
                MsgBox("Error #" & cFtp1.FtpGetLastError & vbCrLf & vbCrLf & cFtp1.GetFtpErrorDescription(cFtp1.FtpGetLastError), MsgBoxStyle.Exclamation)
 
            End If
 
        End If
 
        MsgBox ("DONE.")
 
    End If
 
 
 
End Function
 
 
 
Private Sub lstRemote_DoubleClick(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles lstRemote.DoubleClick
 
    'Redirection:
    
    Dim sDir As String
 
    'Get the dir
    sDir = Trim(VB6.GetItemString(lstRemote, lstRemote.SelectedIndex))
 
    'Clear the list
    lstRemote.Items.Clear()
 
    'Set the remote address
    cmbRemote.Text = cmbRemote.Text & "/" & sDir
 
    'Open the FTP server directory
    cFtp1.PathDir (cmbRemote.Text)
 
End Function
 
 
'************************************************************
'Events:
'************************************************************

Private Sub cFtp1_DownloadProgress(ByVal eventSender As System.Object, ByVal eventArgs As AxFTP_CLIENT_ACTIVEX.__cFtp_DownloadProgressEvent) Handles cFtp1.DownloadProgress
 
    'The download progress
    
    lblDownloadProgress.Text = CStr(eventArgs.lBytes)
 
End Function
 
Private Sub cFtp1_UploadProgress(ByVal eventSender As System.Object, ByVal eventArgs As AxFTP_CLIENT_ACTIVEX.__cFtp_UploadProgressEvent) Handles cFtp1.UploadProgress
 
    'The upload progress
    lblUploadProgress.Text = CStr(eventArgs.lBytes)
 
End Function
 
Private Sub cFtp1_PathEvent(ByVal eventSender As System.Object, ByVal eventArgs As AxFTP_CLIENT_ACTIVEX.__cFtp_PathEvent) Handles cFtp1.PathEvent
 
    'Display current FTP server path
    lstRemote.Items.Add (eventArgs.sName)
 
End Function
 
Private Sub cFtp1_Stat(ByVal eventSender As System.Object, ByVal eventArgs As AxFTP_CLIENT_ACTIVEX.__cFtp_StatEvent) Handles cFtp1.Stat
 
    'The stat of the FTP server connection
    txtStatus.Text = txtStatus.Text & eventArgs.sMessage & vbCrLf
 
End Function
 
 
Private Sub cFtp1_Error(ByVal eventSender As System.Object, ByVal eventArgs As AxFTP_CLIENT_ACTIVEX.__cFtp_ErrorEvent) Handles cFtp1.Error
 
    'Error
    txtStatus.Text = eventArgs.sErrMessage & "(" & eventArgs.lErrNumber & ")" & vbCrLf
 
End Function
 
Private Sub lstRemote_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstRemote.SelectedIndexChanged
 
End Function

ocx

Hello All! I'm the author of ocx-active.com. My website contains many activex components for software developers and software authors. I've decide to put at the 3howto.com some samples of using the components of my website. Enjoy it :)

Post a comment

You must be logged in to post a comment.