ftp call back

Page: code / internet / ftpdownloadcallback.htm

Visual Basic Internet RoutinesFtpFindFirstFile: Download Files via FTP with a Download Progress Callback

Posted: Saturday October 27, 2001Updated: Thursday June 04, 2009

Applies to: VB4-32, VB5, VB6Developed with: VB6, Windows NT4, Windows XP ProOS restrictions: None

Author: VBnet - Randy Birch

Related: URLDownloadToFile: Fast, Simple and Transparent File DownloadsURLDownloadToFile: Fast, Simple and Transparent File Downloads Bypassing the IE Cache

DoFileDownload: Download Files Using IE's Download DialogDoFileDownload: Customize the IE Download Dialog

FtpFindFirstFile: Connect and Retrieve FTP File ListingsFtpFindFirstFile: Download Files via FTP with a Download Progress Callback

Prerequisites

None.

Página 1 de 34[VBnet Internet] FtpFindFirstFile: Download Files via FTP with a Download Progr...

06/12/2011http://vbnet.mvps.org/code/internet/ftpdownloadcallback.htm

FtpFindFirstFile: Connect and Retrieve FTP File Listings showed a straightforward method of navigating folders on a FTP site. FtpGetFile: Download Files via FTP added the ability to download a selected file to the local hard drive.

This demo takes the basic ideas from those demos further by showing how to add a callback to the FTP download method to display the progress of the download in both a regular VB progress bar, as well as in a VBnet 'PhotoShop Flood' style progress bar. In addition, the code shows how to prevent a download from overwriting an existing file of the same name, as well as using the callback to indicate both the status of the FTP activity, as well as the cumulative file size downloaded. If the download is successful, the Photoshop-style progress bar will reflect the success with a green message. If the transfer failed, or if the file existed on the hard drive and the Do Not Overwrite option was selected, the flood will display a red error message.

All the code needed to create the application shown is contained in this page. (Note the screen shots are from Windows XP, and the skinned effect is not part of this demo.) This code page may be wider than most to accommodate the nesting of the routines, as well as the lengthy strings comprising the error messages and Internet constants. The illustration below shows the control layout and labelling for the form. Note that this demo does not require the Winsock control on the form.



BAS Module Code

Add the following additional code to a BAS module:

Option Explicit

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Copyright ©1996-2011 VBnet/Randy Birch, All Rights Reserved.' Some pages may also contain other copyrights by the author.''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Distribution: You can freely use this code in your own' applications, but you may not reproduce ' or publish this code on any web site,' online service, or distribute as source ' on any media without express permission.''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

'persistent handle to the internetPublic hInternet As Long

'persistent handle internet connectionPublic hConnect As Long



'persistent handle internet callback: used to

'determine if necessary to remove before closingPublic hCallback As Long

'string to hold error set in GetECode'on connection, deletion or upload failurePublic FtpErrorMessage As String

'flag used to show/suppress the listing of'the FTP callback messages in List2

Public bFtpShowMessages As Boolean

'default FTP login data

Public Const sFtpUserName As String = "anonymous"Public Const sFtpPassword As String = "[email protected]"

'default local folder for downloadsPublic Const sLocalDownloadPath As String = "d:\ftptest\"

'constants are more efficient than literals'when used in several placesPublic Const sRootDots As String = ".."

Public Const sSlash As String = "/"

'variables for callback

Public dwCurrentFileSize As Double 'file size of downloadPublic pub_BytesSent As Double 'tracks bytes sendPublic pub_BytesRecieved As Double 'tracks bytes received

'misc constants requiredPrivate Const MAX_PATH As Long = 260

Private Const MAXDWORD As Double = (2 ^ 32) - 1Private Const FILE_ATTRIBUTE_ARCHIVE As Long = &H20Private Const WM_SETREDRAW As Long = &HB

Private Const GENERIC_READ As Long = &H80000000Private Const INTERNET_SUCCESS As Long = 1

'use registry configurationPublic Const INTERNET_OPEN_TYPE_PRECONFIG As Long = 0'direct to net

Public Const INTERNET_OPEN_TYPE_DIRECT As Long = 1'via named proxyPublic Const INTERNET_OPEN_TYPE_PROXY As Long = 3

'prevent using java/script/INSPublic Const INTERNET_OPEN_TYPE_PRECONFIG_WITH_NO_AUTOPROXY As Long = 4'used for FTP connections

Public Const INTERNET_FLAG_PASSIVE As Long = &H8000000Public Const INTERNET_FLAG_RELOAD As Long = &H80000000



'Additional cache flags'don't write this item to the cache

Public Const INTERNET_FLAG_NO_CACHE_WRITE As Long = &H4000000Public Const INTERNET_FLAG_DONT_CACHE As Long = INTERNET_FLAG_NO_CACHE_WRITE'make this item persistent in cache

Public Const INTERNET_FLAG_MAKE_PERSISTENT As Long = &H2000000Public Const INTERNET_FLAG_FROM_CACHE As Long = &H1000000'use offline semantics

Public Const INTERNET_FLAG_OFFLINE As Long = INTERNET_FLAG_FROM_CACHE

'Additional flags

'use PCT/SSL if applicable (HTTP)Public Const INTERNET_FLAG_SECURE As Long = &H800000'use keep-alive semantics

Public Const INTERNET_FLAG_KEEP_CONNECTION As Long = &H400000'don't handle redirections automaticallyPublic Const INTERNET_FLAG_NO_AUTO_REDIRECT As Long = &H200000

'do background read prefetchPublic Const INTERNET_FLAG_READ_PREFETCH As Long = &H100000'no automatic cookie handling

Public Const INTERNET_FLAG_NO_COOKIES As Long = &H80000'no automatic authentication handlingPublic Const INTERNET_FLAG_NO_AUTH As Long = &H40000

'return cache file if net request failsPublic Const INTERNET_FLAG_CACHE_IF_NET_FAIL As Long = &H10000'default for FTP servers

Public Const INTERNET_DEFAULT_FTP_PORT As Long = 21' " " gopher "Public Const INTERNET_DEFAULT_GOPHER_PORT As Long = 70

' " " HTTP "Public Const INTERNET_DEFAULT_HTTP_PORT As Long = 80' " " HTTPS "

Public Const INTERNET_DEFAULT_HTTPS_PORT As Long = 443'default for SOCKS firewall servers.Public Const INTERNET_DEFAULT_SOCKS_PORT As Long = 1080

'FTP: use existing InternetConnect handle for server if possiblePublic Const INTERNET_FLAG_EXISTING_CONNECT As Long = &H20000000

Public Const INTERNET_SERVICE_FTP As Long = 1Public Const INTERNET_SERVICE_GOPHER As Long = 2Public Const INTERNET_SERVICE_HTTP As Long = 3

'connected state (mutually exclusive with disconnected)Public Const INTERNET_STATE_CONNECTED As Long = &H1

'disconnected from networkPublic Const INTERNET_STATE_DISCONNECTED As Long = &H2'disconnected by user request

Public Const INTERNET_STATE_DISCONNECTED_BY_USER As Long = &H10'no network requests being made (by Wininet)Public Const INTERNET_STATE_IDLE As Long = &H100



'network requests being made (by Wininet)Public Const INTERNET_STATE_BUSY As Long = &H200

'transfer flagsPrivate Const FTP_TRANSFER_TYPE_UNKNOWN As Long = &H0

Private Const FTP_TRANSFER_TYPE_ASCII As Long = &H1Private Const FTP_TRANSFER_TYPE_BINARY As Long = &H2Private Const INTERNET_FLAG_TRANSFER_ASCII As Long = FTP_TRANSFER_TYPE_ASCII

Private Const INTERNET_FLAG_TRANSFER_BINARY As Long = FTP_TRANSFER_TYPE_BINARYPrivate Const FTP_TRANSFER_TYPE_MASK As Long = (FTP_TRANSFER_TYPE_ASCII Or _ FTP_TRANSFER_TYPE_BINARY)

'imternet callback messagesPublic Const INTERNET_INVALID_STATUS_CALLBACK As Long = -1

Private Const INTERNET_STATUS_RESOLVING_NAME As Long = 10Private Const INTERNET_STATUS_NAME_RESOLVED As Long = 11Private Const INTERNET_STATUS_CONNECTING_TO_SERVER As Long = 20

Private Const INTERNET_STATUS_CONNECTED_TO_SERVER As Long = 21Private Const INTERNET_STATUS_SENDING_REQUEST As Long = 30Private Const INTERNET_STATUS_REQUEST_SENT As Long = 31

Private Const INTERNET_STATUS_RECEIVING_RESPONSE As Long = 40Private Const INTERNET_STATUS_RESPONSE_RECEIVED As Long = 41Private Const INTERNET_STATUS_CTL_RESPONSE_RECEIVED As Long = 42

Private Const INTERNET_STATUS_PREFETCH As Long = 43Private Const INTERNET_STATUS_CLOSING_CONNECTION As Long = 50Private Const INTERNET_STATUS_CONNECTION_CLOSED As Long = 51

Private Const INTERNET_STATUS_HANDLE_CREATED As Long = 60Private Const INTERNET_STATUS_HANDLE_CLOSING As Long = 70Private Const INTERNET_STATUS_DETECTING_PROXY As Long = 80

Private Const INTERNET_STATUS_REQUEST_COMPLETE As Long = 100Private Const INTERNET_STATUS_REDIRECT As Long = 110Private Const INTERNET_STATUS_INTERMEDIATE_RESPONSE As Long = 120

Private Const INTERNET_STATUS_USER_INPUT_REQUIRED As Long = 140Private Const INTERNET_STATUS_STATE_CHANGE As Long = 200

'internet error flagsPrivate Const INTERNET_ERROR_BASE As Long = 12000Private Const ERROR_INTERNET_OUT_OF_HANDLES As Long = (INTERNET_ERROR_BASE + 1)

Private Const ERROR_INTERNET_TIMEOUT As Long = (INTERNET_ERROR_BASE + 2)Private Const ERROR_INTERNET_EXTENDED_ERROR As Long = (INTERNET_ERROR_BASE + 3)Private Const ERROR_INTERNET_INTERNAL_ERROR As Long = (INTERNET_ERROR_BASE + 4)

Private Const ERROR_INTERNET_INVALID_URL As Long = (INTERNET_ERROR_BASE + 5)Private Const ERROR_INTERNET_UNRECOGNIZED_SCHEME As Long = (INTERNET_ERROR_BASE + 6)Private Const ERROR_INTERNET_NAME_NOT_RESOLVED As Long = (INTERNET_ERROR_BASE + 7)

Private Const ERROR_INTERNET_PROTOCOL_NOT_FOUND As Long = (INTERNET_ERROR_BASE + 8)Private Const ERROR_INTERNET_INVALID_OPTION As Long = (INTERNET_ERROR_BASE + 9)Private Const ERROR_INTERNET_BAD_OPTION_LENGTH As Long = (INTERNET_ERROR_BASE + 10)

Private Const ERROR_INTERNET_OPTION_NOT_SETTABLE As Long = (INTERNET_ERROR_BASE + 11)Private Const ERROR_INTERNET_SHUTDOWN As Long = (INTERNET_ERROR_BASE + 12)Private Const ERROR_INTERNET_INCORRECT_USER_NAME As Long = (INTERNET_ERROR_BASE + 13)



Private Const ERROR_INTERNET_INCORRECT_PASSWORD As Long = (INTERNET_ERROR_BASE + 14)Private Const ERROR_INTERNET_LOGIN_FAILURE As Long = (INTERNET_ERROR_BASE + 15)

Private Const ERROR_INTERNET_INVALID_OPERATION As Long = (INTERNET_ERROR_BASE + 16)Private Const ERROR_INTERNET_OPERATION_CANCELLED As Long = (INTERNET_ERROR_BASE + 17)Private Const ERROR_INTERNET_INCORRECT_HANDLE_TYPE As Long = (INTERNET_ERROR_BASE + 18)

Private Const ERROR_INTERNET_INCORRECT_HANDLE_STATE As Long = (INTERNET_ERROR_BASE + 19)Private Const ERROR_INTERNET_NOT_PROXY_REQUEST As Long = (INTERNET_ERROR_BASE + 20)Private Const ERROR_INTERNET_REGISTRY_VALUE_NOT_FOUND As Long = (INTERNET_ERROR_BASE + 21)

Private Const ERROR_INTERNET_BAD_REGISTRY_PARAMETER As Long = (INTERNET_ERROR_BASE + 22)Private Const ERROR_INTERNET_NO_DIRECT_ACCESS As Long = (INTERNET_ERROR_BASE + 23)Private Const ERROR_INTERNET_NO_CONTEXT As Long = (INTERNET_ERROR_BASE + 24)

Private Const ERROR_INTERNET_NO_CALLBACK As Long = (INTERNET_ERROR_BASE + 25)Private Const ERROR_INTERNET_REQUEST_PENDING As Long = (INTERNET_ERROR_BASE + 26)Private Const ERROR_INTERNET_INCORRECT_FORMAT As Long = (INTERNET_ERROR_BASE + 27)

Private Const ERROR_INTERNET_ITEM_NOT_FOUND As Long = (INTERNET_ERROR_BASE + 28)Private Const ERROR_INTERNET_CANNOT_CONNECT As Long = (INTERNET_ERROR_BASE + 29)Private Const ERROR_INTERNET_CONNECTION_ABORTED As Long = (INTERNET_ERROR_BASE + 30)

Private Const ERROR_INTERNET_CONNECTION_RESET As Long = (INTERNET_ERROR_BASE + 31)Private Const ERROR_INTERNET_FORCE_RETRY As Long = (INTERNET_ERROR_BASE + 32)Private Const ERROR_INTERNET_INVALID_PROXY_REQUEST As Long = (INTERNET_ERROR_BASE + 33)

Private Const ERROR_INTERNET_NEED_UI As Long = (INTERNET_ERROR_BASE + 34)Private Const ERROR_INTERNET_HANDLE_EXISTS As Long = (INTERNET_ERROR_BASE + 36)Private Const ERROR_INTERNET_SEC_CERT_DATE_INVALID As Long = (INTERNET_ERROR_BASE + 37)

Private Const ERROR_INTERNET_SEC_CERT_CN_INVALID As Long = (INTERNET_ERROR_BASE + 38)Private Const ERROR_INTERNET_HTTP_TO_HTTPS_ON_REDIR As Long = (INTERNET_ERROR_BASE + 39)Private Const ERROR_INTERNET_HTTPS_TO_HTTP_ON_REDIR As Long = (INTERNET_ERROR_BASE + 40)

Private Const ERROR_INTERNET_MIXED_SECURITY As Long = (INTERNET_ERROR_BASE + 41)Private Const ERROR_INTERNET_CHG_POST_IS_NON_SECURE As Long = (INTERNET_ERROR_BASE + 42)Private Const ERROR_INTERNET_POST_IS_NON_SECURE As Long = (INTERNET_ERROR_BASE + 43)

Private Const ERROR_INTERNET_CLIENT_AUTH_CERT_NEEDED As Long = (INTERNET_ERROR_BASE + 44)Private Const ERROR_INTERNET_INVALID_CA As Long = (INTERNET_ERROR_BASE + 45)Private Const ERROR_INTERNET_CLIENT_AUTH_NOT_SETUP As Long = (INTERNET_ERROR_BASE + 46)

Private Const ERROR_INTERNET_ASYNC_THREAD_FAILED As Long = (INTERNET_ERROR_BASE + 47)Private Const ERROR_INTERNET_REDIRECT_SCHEME_CHANGE As Long = (INTERNET_ERROR_BASE + 48)Private Const ERROR_INTERNET_DIALOG_PENDING As Long = (INTERNET_ERROR_BASE + 49)

Private Const ERROR_INTERNET_RETRY_DIALOG As Long = (INTERNET_ERROR_BASE + 50)Private Const ERROR_INTERNET_HTTPS_HTTP_SUBMIT_REDIR As Long = (INTERNET_ERROR_BASE + 52)Private Const ERROR_INTERNET_INSERT_CD-ROM As Long = (INTERNET_ERROR_BASE + 53)

Private Const ERROR_INTERNET_FORTEZZA_LOGIN_NEEDED As Long = (INTERNET_ERROR_BASE + 54)Private Const ERROR_INTERNET_SEC_CERT_ERRORS As Long = (INTERNET_ERROR_BASE + 55)Private Const ERROR_INTERNET_SEC_CERT_NO_REV As Long = (INTERNET_ERROR_BASE + 56)

Private Const ERROR_INTERNET_SEC_CERT_REV_FAILED As Long = (INTERNET_ERROR_BASE + 57)

'FTP API errors

Private Const ERROR_FTP_TRANSFER_IN_PROGRESS As Long = (INTERNET_ERROR_BASE + 110)Private Const ERROR_FTP_DROPPED As Long = (INTERNET_ERROR_BASE + 111)Private Const ERROR_FTP_NO_PASSIVE_MODE As Long = (INTERNET_ERROR_BASE + 112)

'gopher API errorsPrivate Const ERROR_GOPHER_PROTOCOL_ERROR As Long = (INTERNET_ERROR_BASE + 130)



Private Const ERROR_GOPHER_NOT_FILE As Long = (INTERNET_ERROR_BASE + 131)Private Const ERROR_GOPHER_DATA_ERROR As Long = (INTERNET_ERROR_BASE + 132)

Private Const ERROR_GOPHER_END_OF_DATA As Long = (INTERNET_ERROR_BASE + 133)Private Const ERROR_GOPHER_INVALID_LOCATOR As Long = (INTERNET_ERROR_BASE + 134)Private Const ERROR_GOPHER_INCORRECT_LOCATOR_TYPE As Long = (INTERNET_ERROR_BASE + 135)

Private Const ERROR_GOPHER_NOT_GOPHER_PLUS As Long = (INTERNET_ERROR_BASE + 136)Private Const ERROR_GOPHER_ATTRIBUTE_NOT_FOUND As Long = (INTERNET_ERROR_BASE + 137)Private Const ERROR_GOPHER_UNKNOWN_LOCATOR As Long = (INTERNET_ERROR_BASE + 138)

'HTTP API errorsPrivate Const ERROR_HTTP_HEADER_NOT_FOUND As Long = (INTERNET_ERROR_BASE + 150)

Private Const ERROR_HTTP_DOWNLEVEL_SERVER As Long = (INTERNET_ERROR_BASE + 151)Private Const ERROR_HTTP_INVALID_SERVER_RESPONSE As Long = (INTERNET_ERROR_BASE + 152)Private Const ERROR_HTTP_INVALID_HEADER As Long = (INTERNET_ERROR_BASE + 153)

Private Const ERROR_HTTP_INVALID_QUERY_REQUEST As Long = (INTERNET_ERROR_BASE + 154)Private Const ERROR_HTTP_HEADER_ALREADY_EXISTS As Long = (INTERNET_ERROR_BASE + 155)Private Const ERROR_HTTP_REDIRECT_FAILED As Long = (INTERNET_ERROR_BASE + 156)

Private Const ERROR_HTTP_NOT_REDIRECTED As Long = (INTERNET_ERROR_BASE + 160)Private Const ERROR_HTTP_COOKIE_NEEDS_CONFIRMATION As Long = (INTERNET_ERROR_BASE + 161)Private Const ERROR_HTTP_COOKIE_DECLINED As Long = (INTERNET_ERROR_BASE + 162)

Private Const ERROR_HTTP_REDIRECT_NEEDS_CONFIRMATION As Long = (INTERNET_ERROR_BASE + 168)

'additional Internet API error codes

Private Const ERROR_INTERNET_SECURITY_CHANNEL_ERROR As Long = (INTERNET_ERROR_BASE + 157)Private Const ERROR_INTERNET_UNABLE_TO_CACHE_FILE As Long = (INTERNET_ERROR_BASE + 158)Private Const ERROR_INTERNET_TCPIP_NOT_INSTALLED As Long = (INTERNET_ERROR_BASE + 159)

Private Const ERROR_INTERNET_DISCONNECTED As Long = (INTERNET_ERROR_BASE + 163)Private Const ERROR_INTERNET_SERVER_UNREACHABLE As Long = (INTERNET_ERROR_BASE + 164)Private Const ERROR_INTERNET_PROXY_SERVER_UNREACHABLE As Long = (INTERNET_ERROR_BASE + 165)

Private Const ERROR_INTERNET_BAD_AUTO_PROXY_SCRIPT As Long = (INTERNET_ERROR_BASE + 166)Private Const ERROR_INTERNET_UNABLE_TO_DOWNLOAD_SCRIPT As Long = (INTERNET_ERROR_BASE + 167)Private Const ERROR_INTERNET_SEC_INVALID_CERT As Long = (INTERNET_ERROR_BASE + 169)

Private Const ERROR_INTERNET_SEC_CERT_REVOKED As Long = (INTERNET_ERROR_BASE + 170)

'Internet Autodial specific errors

Private Const ERROR_INTERNET_FAILED_DUETOSECURITYCHECK As Long = (INTERNET_ERROR_BASE + 171)Private Const ERROR_INTERNET_NOT_INITIALIZED As Long = (INTERNET_ERROR_BASE + 172)Private Const ERROR_INTERNET_NEED_MSN_SSPI_PKG As Long = (INTERNET_ERROR_BASE + 173)

Private Const ERROR_INTERNET_LOGIN_FAILURE_DISPLAY_ENTITY_BODY As Long = (INTERNET_ERROR_BASE + 174)Private Const INTERNET_ERROR_LAST = ERROR_INTERNET_FAILED_DUETOSECURITYCHECK

'for the list tabsPublic Const LB_SETTABSTOPS As Long = &H192

'required VB TypesPrivate Type FILETIME dwLowDateTime As Long

dwHighDateTime As LongEnd Type



Public Type WIN32_FIND_DATA dwFileAttributes As Long

ftCreationTime As FILETIME ftLastAccessTime As FILETIME ftLastWriteTime As FILETIME

nFileSizeHigh As Long nFileSizeLow As Long dwReserved0 As Long

dwReserved1 As Long cFileName As String * MAX_PATH cAlternate As String * 14

End Type

Private Type SECURITY_ATTRIBUTES

nLength As Long lpSecurityDescriptor As Long bInheritHandle As Long

End Type

Private Type OVERLAPPED

Internal As Long InternalHigh As Long offset As Long

OffsetHigh As Long hEvent As LongEnd Type

Private Type INTERNET_ASYNC_RESULT dwResult As Long

dwError As LongEnd Type

'required callback enum & varPrivate Enum FTP_STATES FTP_WAIT

FTP_ENUM FTP_DOWNLOAD FTP_DOWNLOADING

FTP_UPLOAD FTP_UPLOADING FTP_CREATINGDIR

FTP_CREATEDIR FTP_REMOVINGDIR FTP_REMOVEDIR

FTP_DELETINGFILE FTP_DELETEFILE FTP_RENAMINGFILE

FTP_RENAMEFILE FTP_ENUMFILESEnd Enum



Private CurrentState As FTP_STATES

Public Declare Function InternetOpen Lib "wininet" _ Alias "InternetOpenA" _

(ByVal lpszAgent As String, _ ByVal dwAccessType As Long, _ ByVal lpszProxyName As String, _

ByVal lpszProxyBypass As String, _ ByVal dwFlags As Long) As Long

Public Declare Function InternetCloseHandle Lib "wininet" _ (ByVal hEnumHandle As Long) As Long

Public Declare Function InternetConnect Lib "wininet" _ Alias "InternetConnectA" _ (ByVal hInternet As Long, _

ByVal lpszServerName As String, _ ByVal nServerPort As Long, _ ByVal lpszUserName As String, _

ByVal lpszPassword As String, _ ByVal dwService As Long, _ ByVal dwFlags As Long, _

ByVal dwContext As Long) As Long

Public Declare Function FtpFindFirstFile Lib "wininet" _

Alias "FtpFindFirstFileA" _ (ByVal hConnect As Long, _ ByVal lpszSearchFile As String, _

lpFindFileData As Any, _ ByVal dwFlags As Long, _ ByVal dwContext As Long) As Long

Private Declare Function InternetFindNextFile Lib "wininet" _ Alias "InternetFindNextFileA" _

(ByVal hFind As Long, _ lpFindFileData As WIN32_FIND_DATA) As Long

Public Declare Function InternetSetStatusCallback Lib "wininet" _ (ByVal hInternet As Long, _ ByVal lpfnInternetCallback As Long) As Long

Private Declare Function InternetGetLastResponseInfo Lib "wininet" _ Alias "InternetGetLastResponseInfoA" _

(lpdwError As Long, _ ByVal lpszBuffer As String, _ lpdwBufferLength As Long) As Long

Private Declare Function FtpGetCurrentDirectory Lib "wininet" _ Alias "FtpGetCurrentDirectoryA" _

Página 10 de 34[VBnet Internet] FtpFindFirstFile: Download Files via FTP with a Download Pro...


(ByVal hConnect As Long, _ ByVal lpszCurrentDirectory As String, _

lpdwCurrentDirectory As Long) As Long

Public Declare Function FtpSetCurrentDirectory Lib "wininet" _

Alias "FtpSetCurrentDirectoryA" _ (ByVal hConnect As Long, _ ByVal lpszDirectory As String) As Long

Private Declare Function FtpGetFileSize Lib "wininet" _ (ByVal hConnect As Long, _

lpdwFileSizeHigh As Long) As Long

Private Declare Function FtpOpenFile Lib "wininet" _

Alias "FtpOpenFileA" _ (ByVal hConnect As Long, _ ByVal lpszFileName As String, _

ByVal dwAccess As Long, _ ByVal dwFlags As Long, _ ByVal dwContext As Long) As Long

Private Declare Function FtpGetFile Lib "wininet" _ Alias "FtpGetFileA" _

(ByVal hConnect As Long, _ ByVal lpszRemoteFile As String, _ ByVal lpszNewFile As String, _

ByVal fFailIfExists As Long, _ ByVal dwFlagsAndAttributes As Long, _ ByVal dwFlags As Long, _

ByVal dwContext As Long) As Long

Public Declare Function SendMessage Lib "user32" _

Alias "SendMessageA" _ (ByVal hwnd As Long, _ ByVal wMsg As Long, _

ByVal wParam As Long, _ lParam As Any) As Long

Private Declare Sub MoveMemory Lib "kernel32" _ Alias "RtlMoveMemory" _ (pTo As Any, _

pFrom As Any, _ ByVal lSize As Long)

Public Declare Function StrFormatByteSizeW Lib "shlwapi.dll " _ (ByVal qdwLow As Long, _ ByVal qdwHigh As Long, _

pwszBuf As Any, _ ByVal cchBuf As Long) As Long



Public Function FtpFileGetFileSize(WFD As WIN32_FIND_DATA) As Double

FtpFileGetFileSize = (WFD.nFileSizeHigh * (MAXDWORD + 1)) + WFD.nFileSizeLow

End Function

Public Function FtpFileGetFileSizeStr(WFD As WIN32_FIND_DATA) As String

Dim sSize As String

sSize = Space$(64) Call StrFormatByteSizeW(WFD.nFileSizeLow, _

WFD.nFileSizeHigh * (MAXDWORD + 1), _ ByVal StrPtr(sSize), 64)

FtpFileGetFileSizeStr = sSize

End Function

Public Function GetInternetConnectHandle() As Long

Dim sServerName As String

'GetInternetConnectHandle obtains a new 'handle expressly for use with the

'FtpFindFirstFile and APIs. ' 'Care must be taken to close only the handle

'returned by this function once the listing 'of the directory has been obtained. '

'A temporary variable is used here 'to reduce line length If hInternet Then

'Pass the same server as with other 'calls, along with the requisite username

'and password. The Microsoft FTP site 'allows anonymous login, so the username 'is 'anonymous' and the password is the

'user's email address. sServerName = frmFtp.Combo1.Text

'return the connection handle GetInternetConnectHandle = InternetConnect(hInternet, _ sServerName, _



0, _ sFtpUserName, _

sFtpPassword, _ INTERNET_SERVICE_FTP, _ INTERNET_FLAG_EXISTING_CONNECT Or _

INTERNET_FLAG_PASSIVE, _ &H0)

End If

End Function

Public Function GetFtpDirectory(hConnect As Long) As String

Dim nCurrDir As Long Dim sCurrDir As String

'FtpGetCurrentDirectory retrieves the current 'directory for the connection. Using this API

'means it is not necessary to track the directory 'hierarchy for navigation.

'pad the requisite buffers sCurrDir = Space$(MAX_PATH) nCurrDir = Len(sCurrDir)

'FtpGetCurrentDirectory returns 1 if successful If FtpGetCurrentDirectory(hConnect, sCurrDir, nCurrDir) = 1 Then

'return a properly qualified path GetFtpDirectory = QualifyUrl(StripNull(sCurrDir))

End If

End Function

Public Function FtpCallbackStatus(ByVal hInternet As Long, _ ByVal dwContext As Long, _ ByVal dwInternetStatus As Long, _

ByVal lpvStatusInfo As Long, _ ByVal dwStatusInfoLength As Long) As Long

Dim sMsg As String Dim cBuffer As String Dim dwRead As Long

Dim uStatus As INTERNET_ASYNC_RESULT

cBuffer = Space$(dwStatusInfoLength)



Select Case dwInternetStatus

Case INTERNET_STATUS_RESOLVING_NAME MoveMemory ByVal cBuffer, ByVal lpvStatusInfo, dwStatusInfoLength sMsg = "Looking up the IP address for " & StripNull(cBuffer)

frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_NAME_RESOLVED

MoveMemory ByVal cBuffer, ByVal lpvStatusInfo, dwStatusInfoLength sMsg = "Name resolved " & StripNull(cBuffer) frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_CONNECTING_TO_SERVER MoveMemory ByVal cBuffer, ByVal lpvStatusInfo, dwStatusInfoLength

sMsg = "Connecting to server..." & StripNull(cBuffer) frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_CONNECTED_TO_SERVER sMsg = "Connected to server." MoveMemory ByVal cBuffer, ByVal lpvStatusInfo, dwStatusInfoLength

sMsg = "Connected to " & StripNull(cBuffer) frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_SENDING_REQUEST

MoveMemory dwRead, ByVal lpvStatusInfo, dwStatusInfoLength

pub_BytesSent = pub_BytesSent + dwRead

Select Case CurrentState Case FTP_UPLOADING

'show the percent complete frmFtp.FloodUpdateTextPC dwCurrentFileSize, _ pub_BytesSent

'the IIf statement assures the 'code will not attempt to set a

'prog bar value greater than Max frmFtp.ProgressBar1.Value = IIf(pub_BytesSent < dwCurrentFileSize, _ pub_BytesSent, _

dwCurrentFileSize)

'if selected, update the list

'with the upload messages If bFtpShowMessages Then sMsg = "Uploading " & _

CStr(pub_BytesSent) & _ " of " & dwCurrentFileSize Call UpdateList(sMsg)



End If

Case Else

sMsg = "Sending request: " & dwRead & " bytes"

Call UpdateList(sMsg)

End Select

Case INTERNET_STATUS_REQUEST_SENT MoveMemory dwRead, ByVal lpvStatusInfo, dwStatusInfoLength

sMsg = "Request sent: " & dwRead & " bytes" pub_BytesSent = pub_BytesSent + dwRead

Case INTERNET_STATUS_RESPONSE_RECEIVED MoveMemory dwRead, ByVal lpvStatusInfo, dwStatusInfoLength pub_BytesRecieved = pub_BytesRecieved + CSng(dwRead)

Select Case CurrentState Case FTP_DOWNLOADING

'show the percent complete frmFtp.FloodUpdateTextPC dwCurrentFileSize, _

pub_BytesRecieved

'the IIf statement assures the

'code will not attempt to set a 'prog bar value greater than Max frmFtp.ProgressBar1.Value = IIf(pub_BytesRecieved < dwCurrentFileSize, _

pub_BytesRecieved, _ dwCurrentFileSize)

'if selected, update the list 'with the upload messages If bFtpShowMessages Then

sMsg = "Downloading " & _ CStr(pub_BytesRecieved) & _ " of " & dwCurrentFileSize

Call UpdateList(sMsg) End If

Case Else sMsg = sMsg = "Response received: " & dwRead & " bytes" Call UpdateList(sMsg)

End Select

Case INTERNET_STATUS_RECEIVING_RESPONSE Case INTERNET_STATUS_CTL_RESPONSE_RECEIVED Case INTERNET_STATUS_PREFETCH



Case INTERNET_STATUS_CLOSING_CONNECTION sMsg = "Closing connection"


Case INTERNET_STATUS_CONNECTION_CLOSED

sMsg = "Connection closed" frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_HANDLE_CREATED MoveMemory dwRead, ByVal lpvStatusInfo, dwStatusInfoLength sMsg = "Handle created: " & CStr(dwRead)


Case INTERNET_STATUS_HANDLE_CLOSING

sMsg = "Handle closed"

If CurrentState = FTP_DOWNLOADING Then

sMsg = "Download complete. " & sMsg CurrentState = FTP_WAIT End If

If CurrentState = FTP_UPLOADING Then sMsg = "Upload complete. " & sMsg

CurrentState = FTP_WAIT End If


Case INTERNET_STATUS_DETECTING_PROXY

sMsg = "Detecting proxy" frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_REQUEST_COMPLETE sMsg = "Request completed" frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_REDIRECT MoveMemory ByVal cBuffer, ByVal lpvStatusInfo, dwStatusInfoLength

sMsg = "HTTP request redirected to " & StripNull(cBuffer) frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATUS_INTERMEDIATE_RESPONSE sMsg = "Received intermediate status message from the server." Call UpdateList(sMsg)

Case INTERNET_STATUS_STATE_CHANGE 'Moved between a secure and a non-secure site.

MoveMemory dwRead, ByVal lpvStatusInfo, dwStatusInfoLength

Select Case dwRead



Case INTERNET_STATE_CONNECTED sMsg = "Connected state moved between secure and nonsecure site"

Case INTERNET_STATE_DISCONNECTED sMsg = "Disconnected from network."


Case INTERNET_STATE_DISCONNECTED_BY_USER

sMsg = "Disconnected by user request." frmFtp.FloodShowConnectAction sMsg

Case INTERNET_STATE_IDLE sMsg = "No network requests are being made (by Wininet)."

Case INTERNET_STATE_BUSY sMsg = "Network requests are being made (by Wininet)."

Case INTERNET_STATUS_USER_INPUT_REQUIRED sMsg = "The request requires user input to complete."

End Select


End Select

' 'upload and download messages are set' 'above as required. This handles the other cases.' If CurrentState <> FTP_UPLOADING And _

' CurrentState <> FTP_DOWNLOADING Then' Call UpdateList(sMsg)' End If

End Function

Public Function FtpFileDownload(sRemoteFile As String, _ sNewLocalFile As String, _

WFD As WIN32_FIND_DATA, _ bFailIfExists As Long) As Boolean

'Show the wait cursor Screen.MousePointer = vbHourglass

'Only if a valid connection... If hConnect Then

'dwCurrentFileSize is used in the 'callback and progress routine dwCurrentFileSize = FtpFileGetFileSize(WFD)



'create the progress window passing the

'upload file size, and a message to display frmFtp.FloodDisplay dwCurrentFileSize, _ "Downloading " & sRemoteFile & _

" to " & sNewLocalFile

'this is the key ... set the current

'FTP state to downloading CurrentState = FTP_DOWNLOADING

'download the file If FtpGetFile(hConnect, _ sRemoteFile, _

sNewLocalFile, _ bFailIfExists, _ FILE_ATTRIBUTE_ARCHIVE, _

FTP_TRANSFER_TYPE_UNKNOWN, _ 1) Then

'show the success message FtpFileDownload = True

Else

'set the error message and return

FtpErrorMessage = GetECode(Err.LastDllError) FtpFileDownload = False

End If 'If FtpGetFile End If 'If hConnect

CurrentState = 0 Screen.MousePointer = vbDefault

End Function

Public Sub GetFtpDirectoryContents()

Dim hFind As Long Dim hFindConnect As Long Dim sPath As String

Dim sPathOnly As String Dim WFD As WIN32_FIND_DATA

'Show the wait cursor Screen.MousePointer = vbHourglass frmFtp.List1.Clear



'Obtain the current FTP path

sPathOnly = GetFtpDirectory(hConnect)

'If the path is not the FTP base directory,

'add ".." to provide a means of navigating 'back up the directory structure. If sPathOnly <> sSlash Then

frmFtp.List1.AddItem sRootDots End If

'The search parameters .. here we'll list 'all file types. Since GetFTPDirectory takes 'care of qualifying the path, no terminating

'slash is required. sPath = sPathOnly & "*.*"

'Connection handles used by the FtpFindFirstFile 'API go out of scope once the all files are 'listed, therefore it can not be reused.

'This restriction is handled by obtaining 'a fresh connection handle each time a call 'to FtpFindFirstFile is required, and releasing

'it once finished. hFindConnect = GetInternetConnectHandle()

'If a good connection handle ... If hFindConnect Then

'..obtain the handle to the files with 'the FtpFindFirstFile API. Obtaining the 'directory contents is essentially similar

'to using the Win32 file system APIs 'FindFirstFile and FindNextFile, with the 'sole exception that there is no FtpFindNextFile

'API. Instead, successive calls are made 'to InternetFindNextFile. The data returned 'is in the familiar WIN32_FIND_DATA structure.

hFind = FtpFindFirstFile(hFindConnect, _ sPath, WFD, _ INTERNET_FLAG_RELOAD Or _

INTERNET_FLAG_NO_CACHE_WRITE, _ 0&)

'If a valid find handle returned, 'loop through the directory listing 'the contents. If the attributes of

'the returned string indicate a folder, 'append a slash to make it both visually 'stand out in the list, and identifiable



'in the list double-click routine for 'navigation.

' 'hFile will be 0 if the navigated-to 'folder is empty.

If hFind Then

'suspend redraw on the file list

Call SendMessage(frmFtp.List1.hwnd, _ WM_SETREDRAW, _ 0&, ByVal 0&)

Do

'if a folder If WFD.dwFileAttributes And vbDirectory Then

'append a slash and add to list frmFtp.List1.AddItem QualifyUrl(StripNull(WFD.cFileName))

Else

'add the item and its file size

frmFtp.List1.AddItem StripNull(WFD.cFileName) & _ vbTab & _ FtpFileGetFileSizeStr(WFD)

End If 'If WFD.dwFileAttributes

frmFtp.List1.Refresh

'continue while valid

Loop While InternetFindNextFile(hFind, WFD)

Call SendMessage(frmFtp.List1.hwnd, _

WM_SETREDRAW, _ True, ByVal 0&)

End If 'If hFind

End If 'If hFindConnect

'clean up by closing the handles used in this routine Call InternetCloseHandle(hFind)

Call InternetCloseHandle(hFindConnect)

Screen.MousePointer = vbDefault

End Sub



Public Function GetECode(ByVal lErrorCode As Long) As String

'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' From : MSDN

' Name : GetECode' Purpose : Provides message corresponding to DLL error codes' Parameters : The DLL error code

' Return val : String containing message' Algorithm : Selects the appropriate string'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

Dim sBuffer As String Dim nBuffer As Long

Select Case lErrorCode Case 12001: GetECode = "No more handles could be generated at this time"

Case 12002: GetECode = "The request has timed out." Case 12003:

'extended error. Retrieve the details using

'the InternetGetLastResponseInfo API.

sBuffer = Space$(256)

nBuffer = Len(sBuffer)

If InternetGetLastResponseInfo(lErrorCode, sBuffer, nBuffer) Then

GetECode = StripNull(sBuffer) Else GetECode = "Extended error returned from server."

End If

Case 12004: GetECode = "An internal error has occurred."

Case 12005: GetECode = "URL is invalid." Case 12006: GetECode = "URL scheme could not be recognized, " & _ "or is not supported."

Case 12007: GetECode = "Server name could not be resolved." Case 12008: GetECode = "Requested protocol could not be located." Case 12009: GetECode = "A request to InternetQueryOption or " & _

"InternetSetOption specified an invalid option value." Case 12010: GetECode = "Length of an option supplied to InternetQueryOption " & _ "or InternetSetOption is incorrect for the type " & _

"of option specified." Case 12011: GetECode = "The request option can not be set, only queried. " Case 12012: GetECode = "The Win32 Internet support is being shutdown or unloaded."

Case 12013: GetECode = "Request to connect and login to an FTP server could not" & _ "be completed because the supplied user name is incorrect." Case 12014: GetECode = "Request to connect and login to an FTP server could not " & _

"be completed because the supplied password is incorrect. " Case 12015: GetECode = "Request to connect to and login to an FTP server failed." Case 12016: GetECode = "Requested operation is invalid. "



Case 12017: GetECode = "Operation was cancelled, usually because the handle on " & _ "which the request was operating was closed before the " & _

"operation completed." Case 12018: GetECode = "Type of handle supplied is incorrect for this operation." Case 12019: GetECode = "Requested operation can not be carried out because the " & _

"handle supplied is not in the correct state." Case 12020: GetECode = "Request can not be made via a proxy." Case 12021: GetECode = "A required registry value could not be located. "

Case 12022: GetECode = "A required registry value was located but is an " & _ "incorrect type or has an invalid value." Case 12023: GetECode = "Direct network access cannot be made at this time. "

Case 12024: GetECode = "An asynchronous request could not be made because " & _ "a zero context value was supplied." Case 12025: GetECode = "An asynchronous request could not be made because " & _

"a callback function has not been set." Case 12026: GetECode = "The required operation could not be completed " & _ "because one or more requests are pending."

Case 12027: GetECode = "The format of the request is invalid." Case 12028: GetECode = "The requested item could not be located." Case 12029: GetECode = "The attempt to connect to the server failed."

Case 12030: GetECode = "The connection with the server has been terminated." Case 12031: GetECode = "The connection with the server has been reset." Case 12036: GetECode = "The request failed because the handle already exists."

Case Else: GetECode = "Error details not available." End Select

End Function

Public Function StripNull(item As String)

'return a string without the chr$(0) terminator

Dim pos As Long

pos = InStr(item, Chr$(0))

If pos Then StripNull = Left$(item, pos - 1)

Else StripNull = item End If

End Function

Public Function QualifyPath(sPath As String) As String

'assures that a passed path ends in a slash If Right$(sPath, 1) <> "\" Then QualifyPath = sPath & "\"



Else QualifyPath = sPath End If

End Function

Public Function QualifyUrl(sPath As String) As String

'assures that a passed URL ends in a slash If Right$(sPath, 1) <> "/" Then QualifyUrl = sPath & "/" Else QualifyUrl = sPath End If

End Function

Private Sub UpdateList(sMsg As String)

'if showing messages, add the new 'item and scroll the list to keep

'in view. If bFtpShowMessages Then frmFtp.List2.AddItem sMsg

frmFtp.List2.TopIndex = frmFtp.List2.NewIndex End If

End Sub

Form Code

As shown in the illustrations above, to a new form add:

Four command buttons (Command1 - Command4) Two lists (List1, List2) Three Labels (lblStatus, Label2, Label3) A VB picture box (tbFlood) to act as the Photoshop flood bar. A VB progress bar (ProgressBar1) Two Check boxes (Check1, Check2) A combo box (Combo1)

.... add the following code:

Option Explicit



Private sProgressMessage As StringDim f As PictureBox

Private Sub Form_Load()

Me.Move (Screen.Width - Me.Width) \ 2, (Screen.Height - Me.Height) \ 2.6

Label2.Caption = "Closed" Label3.Caption = "No connection" Text1.Text = ""

lblStatus.Caption = "" Command2.Enabled = False Command3.Enabled = False

Command4.Enabled = False tbFlood.AutoRedraw = True 'else we won't see the progress!

Check2.Value = 1

'tabs for the file/folder and size display

ReDim TabArray(0 To 0) As Long TabArray(0) = 142

'Clear existing tabs and set the tabs Call SendMessage(List1.hwnd, LB_SETTABSTOPS, 0&, ByVal 0&) Call SendMessage(List1.hwnd, LB_SETTABSTOPS, 1&, TabArray(0))

List1.Refresh

With Combo1

.AddItem "127.0.0.1" 'localhost .AddItem "ftp.microsoft.com" .AddItem "ftp.netscape.com"

.AddItem "ftp.sun.com" .AddItem "www.technolog.fr" .AddItem "www.winfiles.com"

.AddItem "olivo.mentor.mec.es" .AddItem "main.amu.edu.pl" .AddItem "tucows.com" 'demonstrates error

.ListIndex = 0 End With

Command1.Caption = "Open Connction" Command2.Caption = "Close Connction" Command3.Caption = "Download"

Command4.Caption = "FtpFindFirstFile"

End Sub

Private Sub Form_Unload(Cancel As Integer)



'if the handles are still valid,

'clean up before exiting

If (hCallback <> INTERNET_INVALID_STATUS_CALLBACK) And _

(hCallback <> 0) And _ hInternet Then

'remove the current callback Call InternetSetStatusCallback(hCallback, 0&) End If

If hConnect Then InternetCloseHandle (hConnect) If hInternet Then InternetCloseHandle (hInternet)

End Sub

Private Sub Command1_Click()

Dim sServerName As String

'Show the wait cursor

Screen.MousePointer = vbHourglass

'Begin the FTP process by obtaining a

'handle to an internet session. This 'handle will be used in subsequent calls, 'so its declared as a form-wide variable.

hInternet = InternetOpen("VBnet FTP Transfer", _ INTERNET_OPEN_TYPE_DIRECT, _ vbNullString, _

vbNullString, _ INTERNET_FLAG_NO_CACHE_WRITE)

'If a handle was obtained, the next step is 'to obtain a connection handle that will be

'used for all operations except the FTP 'directory navigation. The MSDN states that 'the handle used by FtpFindFirstFile and subsequent

'file calls can not be reused for additional 'navigation or other operations. If hInternet Then

'create the callback to handle user 'actions and reflect status codes

hCallback = InternetSetStatusCallback(hInternet, _ AddressOf FtpCallbackStatus)



'if successful, hCallback will be either zero 'if this is the first call, or the handle of

'the previously started callback. It will 'be -1 if invalid. If hCallback <> INTERNET_INVALID_STATUS_CALLBACK Then

sServerName = Combo1.Text

'get a connection handle hConnect = InternetConnect(hInternet, _ sServerName, _

INTERNET_DEFAULT_FTP_PORT, _ sFtpUserName, _ sFtpPassword, _

INTERNET_SERVICE_FTP, _ INTERNET_FLAG_EXISTING_CONNECT Or _ INTERNET_FLAG_PASSIVE, _

1&)

'if the connection handle is valid, get

'the current FTP directory If hConnect <> 0 Then

'reflect the current path in the 'text box (it should be '\' ) and 'get the directory contents

Text1.Text = GetFtpDirectory(hConnect) Call GetFtpDirectoryContents

Else

'show the error

lblStatus.Caption = GetECode(Err.LastDllError)

End If 'If hConnect

End If 'If InternetSetStatusCallback

End If 'If hInternet

'display the session handles

Label3.Caption = hInternet Label2.Caption = hConnect

'If both handles are valid, disable the Open button 'and enable the FTP button. If *either* handle is 'valid, enable the close button. The download

'button is false. Command1.Enabled = (hInternet = 0) And (hConnect = 0) Command2.Enabled = (hInternet <> 0) And (hConnect <> 0)



Command3.Enabled = (hInternet <> 0) Or (hConnect <> 0) Command4.Enabled = False

Combo1.Enabled = (hInternet = 0) And (hConnect = 0)

Screen.MousePointer = vbDefault

End Sub


'clean up Call InternetCloseHandle(hConnect) Call InternetCloseHandle(hInternet)

hInternet = 0 hConnect = 0

Label2.Caption = "Closed" Label3.Caption = "No connection"

'If both handles are valid, enable the Open button 'and disable the FTP button. If *either* handle is

'valid, disable the close button. The download 'button is disabled. Command1.Enabled = (hInternet = 0) And (hConnect = 0)

Command2.Enabled = (hInternet <> 0) And (hConnect <> 0) Command3.Enabled = (hInternet <> 0) Or (hConnect <> 0) Command4.Enabled = False

Combo1.Enabled = True lblStatus.Caption = ""

List1.Clear Combo1.SetFocus

End Sub


Dim sFile As String

Dim sCurrDir As String Dim sRemoteFile As String Dim sNewLocalFile As String

Dim hFind As Long Dim hFindConnect As Long Dim WFD As WIN32_FIND_DATA

Dim success As Boolean

'this just resets the list, labels and error message



ResetStuff

If hConnect Then

'get the current directory and

'selected list item sCurrDir = GetFtpDirectory(hConnect) sFile = ParseFileFromList(List1.List(List1.ListIndex))

'build the necessary strings. The 'directory is qualified, so contains

'the terminating slash. sRemoteFile = sCurrDir & sFile sNewLocalFile = QualifyPath(sLocalDownloadPath) & sFile

'assure the file is on the server and retrieving 'its info into a WIN32_FIND_DATA structure

hFindConnect = GetInternetConnectHandle() hFind = FtpFindFirstFile(hFindConnect, _ sRemoteFile & vbNullString, _

WFD, 0&, 0&) lblStatus.Caption = Err.LastDllError

'if the FtpFindFirstFile call located 'the file then download If hFind <> 0 Then

success = FtpFileDownload(sRemoteFile, _ sNewLocalFile, _

WFD, _ (Check1.Value = 1)) 'if 1 then will not overwrite

FloodShowTransferResult success, sNewLocalFile

End If

'clean up Call InternetCloseHandle(hFind)

Call InternetCloseHandle(hFindConnect)

End If

End Sub


Call GetFtpDirectoryContents



End Sub

Private Sub Check2_Click()

bFtpShowMessages = Check2.Value = 1

End Sub

Private Sub Combo1_Click()

Combo1 = Combo1.Text

End Sub

Private Sub List1_Click()

Dim sNewPath As String

'get the desired directory from the list sNewPath = List1.List(List1.ListIndex)

'if a root item or directory is selected, 'disable the download button

Command4.Enabled = (Right$(sNewPath, 1) <> sSlash) And _ (sNewPath <> sRootDots)

End Sub

Private Sub List1_DblClick()

Dim sNewPath As String

Dim sPath As String

'get the desired directory from the list

sNewPath = List1.List(List1.ListIndex)

'If a root item selected, exit; the routine

'will navigate a level higher. If it is 'a file, we don't want to navigate. If sNewPath <> sRootDots And Right$(sNewPath, 1) <> sSlash Then

'root or file selected Exit Sub

Else



'Show the wait cursor Screen.MousePointer = vbHourglass

'clear the list in preparation for 'retrieving the directory contents

List1.Clear

'retrieve the current FTP path

'using GetFTPDirectory sPath = GetFtpDirectory(hConnect)

'qualify it if necessary, and append 'the new path to it If Right$(sPath, 1) <> sSlash Then

sPath = sPath & sSlash & sNewPath Else sPath = sPath & sNewPath

End If

'set the new path using the

'FtpSetCurrentDirectory API Call FtpSetCurrentDirectory(hConnect, sPath)

'reflect the new path in the text box Text1.Text = GetFtpDirectory(hConnect)

'reload the list with the current directory GetFtpDirectoryContents

'Show the wait cursor Screen.MousePointer = vbDefault

End If

End Sub

'the Flood methods are Public as they're called from 'the BAS module to update the download progress barPublic Sub FloodDisplay(upperLimit, floodMessage As String)

'set the module-level variable f 'equal to the parent form flood panel Set f = tbFlood

'initialize the control by setting: 'white (the text colour)

'black (the flood panel colour) 'not Xor pen 'solid fill



f.Cls f.BackColor = &HFFFFFF

f.ForeColor = &H800000 f.DrawMode = 10 f.FillStyle = 0

'set the scalewidth equal to the 'upper limit of the items to count

f.ScaleWidth = upperLimit

f.Cls

f.Visible = True

'set a form-level variable for the flood message

'to avoid the need for continually passing a string sProgressMessage = floodMessage

frmFtp.ProgressBar1.Max = upperLimit frmFtp.ProgressBar1.Min = 0 frmFtp.ProgressBar1.Value = 0

End Sub

Public Sub FloodHide()

f.Visible = False f.Cls

'free the memory used by f Set f = Nothing

End Sub

Public Sub FloodUpdateTextPC(upperLimit As Double, progress As Double)

Dim pc As String

If progress <= upperLimit Then

If progress > tbFlood.ScaleWidth Then progress = tbFlood.ScaleWidth

tbFlood.Cls

tbFlood.ScaleWidth = upperLimit

'format the progress into a percentage string to display

pc = Format$(CLng((progress / tbFlood.ScaleWidth) * 100)) + "%"

'calculate the string's X & Y coordinates



'in the PictureBox ... here, left justified and offset slightly tbFlood.CurrentX = 2

tbFlood.CurrentY = (tbFlood.ScaleHeight - tbFlood.TextHeight(sProgressMessage)) \ 2

'print the percentage string in the text colour

tbFlood.Print sProgressMessage & " " & pc

'print the flood bar to the new progress length in the line colour

tbFlood.Line (0, 0)-(progress, tbFlood.ScaleHeight), tbFlood.ForeColor, BF

'without this DoEvents or Refresh, the flood won't update

tbFlood.Refresh

End If

End Sub

Public Sub FloodShowTransferResult(success As Boolean, sFile As String)

Dim sMsg As String

Select Case success

Case True: tbFlood.BackColor = &HFFFFFF tbFlood.ForeColor = &H3A633D

sMsg = "Transfer of " & sFile & " completed successfully." Case False: tbFlood.BackColor = &HFFFFFF

tbFlood.ForeColor = &H3D2785 sMsg = "Transfer of " & sFile & " failed." End Select

tbFlood.Cls

'calculate the string's X & Y coordinates 'in the Picture Box ... here, left justified and offset slightly tbFlood.CurrentX = 2

tbFlood.CurrentY = (tbFlood.ScaleHeight - tbFlood.TextHeight(sMsg )) \ 2

'print the percentage string in the text colour

tbFlood.Print sMsg

'print the flood bar to the new progress length in the line colour

tbFlood.Line (0, 0)-(tbFlood.ScaleWidth, tbFlood.ScaleHeight), tbFlood.ForeColor, BF

End Sub

Public Sub FloodShowConnectAction(sConnectMsg As String)



tbFlood.Cls

'calculate the string's X & Y coordinates 'in the PictureBox ... here, left justified and offset slightly tbFlood.CurrentX = 2 tbFlood.CurrentY = (tbFlood.ScaleHeight - tbFlood.TextHeight(sConnectMsg)) \ 2

tbFlood.BackColor = &HFFFFFF tbFlood.ForeColor = &H800000

'print the percentage string in the text colour tbFlood.Print sConnectMsg

End Sub

Private Sub ResetStuff()

List2.Clear

lblStatus.Caption = ""

FtpErrorMessage = ""

pub_BytesSent = 0

pub_BytesRecieved = 0

End Sub

Private Function ParseFileFromList(ByVal sSelection As String) As String

Dim pos As Long

pos = InStr(sSelection, vbTab)

If pos Then

ParseFileFromList = Left$(sSelection, pos - 1) Else ParseFileFromList = sSelection

End If

End Function

Comments

Select a download site from the combo, and navigate to a file of interest. Hit download to save the file to your local drive. Remember to set the local save path to a valid folder on your machine.



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