baralong
asked on
Posting a file to an HTTP server
I have a CGI type web page that recieves an image file from a form that looks like:
<form enctype="multipart/form-da
<input name="my_file" type="file" size="20">
</form>
The server accepts the file and saves it.
This works fine when posted from a web page but I need to be able to invoke it from VB. I've been trying to use the Internet Transfer Control with an Execute command but with no luck.
I don't have the option to transfer the file using FTP.
Thanks
<form enctype="multipart/form-da
<input name="my_file" type="file" size="20">
</form>
The server accepts the file and saves it.
This works fine when posted from a web page but I need to be able to invoke it from VB. I've been trying to use the Internet Transfer Control with an Execute command but with no luck.
I don't have the option to transfer the file using FTP.
Thanks
ASKER
Adjusted points to 1000
The easiest way is to use the WebBrowser control. Create a html file with your form and show it in the control. It is possible to submit your form with the Document property of this control.
Using the Navigate method of the webbrowser control you can send data...
To add this control to your program, right-click on the toolbox and select "Components..." then select "Microsoft Internet Controls" (SHDOCVW.DLL) from the Controls box.
The help file for this control is not installed on your system, but it is on the Visual Basic CD, in the directory:
\TOOLS\UNSUPPRT\WEBBRWSR
Here is the help page for navigate:
NAVIGATE METHOD
Navigates to the resource identified by a Universal Resource Locator (URL), or to the file identified by a full path.
Syntax
object.Navigate url, flags, TargetFrameName, PostData, Headers
The GetProperty method syntax has these parts:
Part Description
object An object expression that evaluates to an object in the Applies To list.
Url Required. A string expression that evaluates to the URL of the resource to display, or the full path of the file to display.
Flags Optional. A constant or value that specifies whether to add the resource to the history list, whether to read from or write to the cache, and whether to display the resource in a new window. It can be a combination of the following values. See Settings below.
TargetFrameName Optional. A string expression that evaluates to the name of a frame in which to display the resource.
PostData Optional. Data to send to the server during the HTTP POST transaction. For example, the POST transaction is used to send data gathered by an HTML form. If this parameter does not specify any post data, the Navigate method issues an HTTP GET transaction. This parameter is ignored if URL is not an HTTP URL.
Headers Optional. A value that specifies additional HTTP headers to send to the server. These headers are added to the default Internet Explorer headers. The headers can specify such things as the action required of the server, the type of data being passed to the server, or a status code. This parameter is ignored if URL is not an HTTP URL.
Settings
The settings for flags are:
Constant Value Description
navOpenInNewWindow 1 Open the resource or file in a new window.
navNoHistory 2 Do not add the resource or file to the history list. The new page replaces the current page in the list.
navNoReadFromCache 4 Do not read from the disk cache for this navigation.
navNoWriteToCache 8 Do not write the results of this navigation to the disk cache.
Cheers!
To add this control to your program, right-click on the toolbox and select "Components..." then select "Microsoft Internet Controls" (SHDOCVW.DLL) from the Controls box.
The help file for this control is not installed on your system, but it is on the Visual Basic CD, in the directory:
\TOOLS\UNSUPPRT\WEBBRWSR
Here is the help page for navigate:
NAVIGATE METHOD
Navigates to the resource identified by a Universal Resource Locator (URL), or to the file identified by a full path.
Syntax
object.Navigate url, flags, TargetFrameName, PostData, Headers
The GetProperty method syntax has these parts:
Part Description
object An object expression that evaluates to an object in the Applies To list.
Url Required. A string expression that evaluates to the URL of the resource to display, or the full path of the file to display.
Flags Optional. A constant or value that specifies whether to add the resource to the history list, whether to read from or write to the cache, and whether to display the resource in a new window. It can be a combination of the following values. See Settings below.
TargetFrameName Optional. A string expression that evaluates to the name of a frame in which to display the resource.
PostData Optional. Data to send to the server during the HTTP POST transaction. For example, the POST transaction is used to send data gathered by an HTML form. If this parameter does not specify any post data, the Navigate method issues an HTTP GET transaction. This parameter is ignored if URL is not an HTTP URL.
Headers Optional. A value that specifies additional HTTP headers to send to the server. These headers are added to the default Internet Explorer headers. The headers can specify such things as the action required of the server, the type of data being passed to the server, or a status code. This parameter is ignored if URL is not an HTTP URL.
Settings
The settings for flags are:
Constant Value Description
navOpenInNewWindow 1 Open the resource or file in a new window.
navNoHistory 2 Do not add the resource or file to the history list. The new page replaces the current page in the list.
navNoReadFromCache 4 Do not read from the disk cache for this navigation.
navNoWriteToCache 8 Do not write the results of this navigation to the disk cache.
Cheers!
mcrider, your method is too hard - you have to encode the file and do all other stuff yourself while it can be done by the WebBrowser control... And your answer is very incomplete, please post such answers as comments.
vmv, I know when to post an answer... I suggest you find my name in the top 15 experts in this category.
As for having to URLencode the Post buffer being sent, Adding the following to a module and calling the URLencode function will accomplish this.
Function ReplaceInString(Source As String, TheString As String, TheReplaceString As String) As String
Dim iVal As Integer
Dim Workspace As String
Workspace = Source
iVal = 1
Do
iVal = InStr(iVal, Workspace, TheString, 1)
If iVal = 0 Then Exit Do
Workspace = Left$(Workspace, iVal - 1) + TheReplaceString + Mid$(Workspace, iVal + Len(TheString))
iVal = iVal + 1
Loop
ReplaceInString = Workspace
End Function
Function StripHTML(Source As String) As String
Dim iVal As Long
Dim Buf As String
Dim lBuf As String
Dim rBbuf As String
iVal = InStr(1, Source, "<")
If iVal = 0 Then
StripHTML = Source
Exit Function
End If
lBuf = Left$(Source, iVal - 1)
iVal = InStr(iVal, Source, ">")
rbuf = Mid$(Source, iVal + 1)
Buf = lBuf + " " + rbuf
Do
iVal = InStr(1, Buf, "<")
If iVal = 0 Then
StripHTML = Buf
Exit Do
End If
lBuf = Left$(Buf, iVal - 1)
iVal = InStr(iVal, Buf, ">")
rbuf = Mid$(Buf, iVal + 1)
Buf = lBuf + " " + rbuf
Loop
End Function
Function URLdecode(Source As String) As String
Dim lBuf As String
Dim iVal As Long
lBuf = ReplaceInString(Source, "+", " ")
iVal = 1
Do
iVal = InStr(iVal, lBuf, "%")
If iVal = 0 Then Exit Do
lBuf = Left$(lBuf, iVal - 1) _
+ Chr$(CLng("&H" + Mid$(lBuf, iVal + 1, 2))) _
+ Mid$(lBuf, iVal + 3)
iVal = iVal + 1
Loop
URLdecode = lBuf
End Function
Function URLencode(Source As String) As String
Dim iVal As Long
Dim lBuf As String
Dim lArray As Variant
lBuf = Source
For Each lArray In Array("%", "&", "+", "~", "`", "!", "@", "#", "$", "^", "*" _
, "(", ")", "-", "_", "=", "{", "[", "}", "]", "|", "\", ":", ";", "'", "<" _
, ">", "?", ",", ".", "/", Chr$(34))
lBuf = ReplaceInString(lBuf, CStr(lArray), "%" + Right$("0" + Hex(Asc(lArray)), 2))
Next
lBuf = ReplaceInString(lBuf, " ", "+")
iVal = 0
Do
iVal = iVal + 1
If iVal > Len(lBuf) Then Exit Do
lArray = Mid$(lBuf, iVal, 1)
If Asc(lArray) <= 31 Or Asc(lArray) >= 127 Then
lBuf = ReplaceInString(lBuf, CStr(lArray), "%" + Right$("0" + Hex(Asc(lArray)), 2))
End If
Loop
URLencode = lBuf
End Function
As for having to URLencode the Post buffer being sent, Adding the following to a module and calling the URLencode function will accomplish this.
Function ReplaceInString(Source As String, TheString As String, TheReplaceString As String) As String
Dim iVal As Integer
Dim Workspace As String
Workspace = Source
iVal = 1
Do
iVal = InStr(iVal, Workspace, TheString, 1)
If iVal = 0 Then Exit Do
Workspace = Left$(Workspace, iVal - 1) + TheReplaceString + Mid$(Workspace, iVal + Len(TheString))
iVal = iVal + 1
Loop
ReplaceInString = Workspace
End Function
Function StripHTML(Source As String) As String
Dim iVal As Long
Dim Buf As String
Dim lBuf As String
Dim rBbuf As String
iVal = InStr(1, Source, "<")
If iVal = 0 Then
StripHTML = Source
Exit Function
End If
lBuf = Left$(Source, iVal - 1)
iVal = InStr(iVal, Source, ">")
rbuf = Mid$(Source, iVal + 1)
Buf = lBuf + " " + rbuf
Do
iVal = InStr(1, Buf, "<")
If iVal = 0 Then
StripHTML = Buf
Exit Do
End If
lBuf = Left$(Buf, iVal - 1)
iVal = InStr(iVal, Buf, ">")
rbuf = Mid$(Buf, iVal + 1)
Buf = lBuf + " " + rbuf
Loop
End Function
Function URLdecode(Source As String) As String
Dim lBuf As String
Dim iVal As Long
lBuf = ReplaceInString(Source, "+", " ")
iVal = 1
Do
iVal = InStr(iVal, lBuf, "%")
If iVal = 0 Then Exit Do
lBuf = Left$(lBuf, iVal - 1) _
+ Chr$(CLng("&H" + Mid$(lBuf, iVal + 1, 2))) _
+ Mid$(lBuf, iVal + 3)
iVal = iVal + 1
Loop
URLdecode = lBuf
End Function
Function URLencode(Source As String) As String
Dim iVal As Long
Dim lBuf As String
Dim lArray As Variant
lBuf = Source
For Each lArray In Array("%", "&", "+", "~", "`", "!", "@", "#", "$", "^", "*" _
, "(", ")", "-", "_", "=", "{", "[", "}", "]", "|", "\", ":", ";", "'", "<" _
, ">", "?", ",", ".", "/", Chr$(34))
lBuf = ReplaceInString(lBuf, CStr(lArray), "%" + Right$("0" + Hex(Asc(lArray)), 2))
Next
lBuf = ReplaceInString(lBuf, " ", "+")
iVal = 0
Do
iVal = iVal + 1
If iVal > Len(lBuf) Then Exit Do
lArray = Mid$(lBuf, iVal, 1)
If Asc(lArray) <= 31 Or Asc(lArray) >= 127 Then
lBuf = ReplaceInString(lBuf, CStr(lArray), "%" + Right$("0" + Hex(Asc(lArray)), 2))
End If
Loop
URLencode = lBuf
End Function
mcrider,
>I suggest you find my name in the top 15 experts in this category.
This just means that you was here for a long time posting comments as answers.
>As for having to URLencode the Post buffer
Why you want to write kilobytes of unneded (maybe buggy) code while all this stuff is already implemented in the WebBrowser? Why you don't post assembly source for this?
>I suggest you find my name in the top 15 experts in this category.
This just means that you was here for a long time posting comments as answers.
>As for having to URLencode the Post buffer
Why you want to write kilobytes of unneded (maybe buggy) code while all this stuff is already implemented in the WebBrowser? Why you don't post assembly source for this?
ASKER
Thanks for the help so far.
mcrider, I don't see how any of the functions help me send a binary file. I realise I need to encode the file but how?
I haven't had a chance to try either approach out, and won't until Monday.
mcrider, I don't see how any of the functions help me send a binary file. I realise I need to encode the file but how?
I haven't had a chance to try either approach out, and won't until Monday.
baralong,
Basically, you do this:
Dim PostData As String
Dim FileData As String
'Put your code to read the file into the string variable "FileData" here...
'Convert the string into a URL Encoded string...
PostData = URLencode(FileData)
'Send the encoded data to your server...
WebBrowser1.Navigate "http://server/accept.pl", , , PostData
Cheers!
Basically, you do this:
Dim PostData As String
Dim FileData As String
'Put your code to read the file into the string variable "FileData" here...
'Convert the string into a URL Encoded string...
PostData = URLencode(FileData)
'Send the encoded data to your server...
WebBrowser1.Navigate "http://server/accept.pl", , , PostData
Cheers!
ASKER
mcrider, sorry but I can't get this to work. My CGI script can't doesn't recieve the file correctly
vmv, your method seems promising. I have to admit I'm quite a novice when it comes to VB so I'm probably making this more complex than it needs to be.
The problem I'm having with this is: I get the Document property but can't seem to get any lower, I thought it would be an "HTMLDocument" but it's not working well.
if the form detail is:
<form enctype="multipart/form-da
<input name="my_file" type="file" size="20" id="my_file">
<input type="submit" id="sub">
</form>
can you post code to set the value of "my_file" and then submit the form.
I have been trying with:
Dim HTMLDoc As HTMLDocument
Set HTMLDoc = WB.Document ' OK up to here
Dim Elem As HTMLFormElement
Set Elem = HTMLDoc.Forms("form1") ' here is where it breaks.
Thanks
vmv, your method seems promising. I have to admit I'm quite a novice when it comes to VB so I'm probably making this more complex than it needs to be.
The problem I'm having with this is: I get the Document property but can't seem to get any lower, I thought it would be an "HTMLDocument" but it's not working well.
if the form detail is:
<form enctype="multipart/form-da
<input name="my_file" type="file" size="20" id="my_file">
<input type="submit" id="sub">
</form>
can you post code to set the value of "my_file" and then submit the form.
I have been trying with:
Dim HTMLDoc As HTMLDocument
Set HTMLDoc = WB.Document ' OK up to here
Dim Elem As HTMLFormElement
Set Elem = HTMLDoc.Forms("form1") ' here is where it breaks.
Thanks
baralong,
Post a copy of your perl CGI script...
Cheers!®©
Post a copy of your perl CGI script...
Cheers!®©
Unfortunately I never tried to do something similar, so I don't know how to get this to work - that comment was just an idea of a way to work on. I suggest you to look for some example in the MSDN.
baralong,
If you dont have Service Pack 2 or 3 installed, the INET "post" will not work. See the following microsoft KB articles:
FIX: Internet Transfer Control 5.0 "POST" Request Doesn't Work
http://support.microsoft.com/support/kb/articles/Q167/7/06.asp?LNG=ENG&SA=MSDN&FR=0
INFO: Visual Studio 97 Service Packs - What, Where, and Why
http://support.microsoft.com/support/kb/articles/Q170/3/65.ASP
INFO: Visual Basic 5.0 Fixes in Visual Studio 97 Service Pack 2
http://support.microsoft.com/support/kb/articles/Q171/5/54.asp?LNG=ENG&SA=MSDN&FR=0
Cheers!®©
If you dont have Service Pack 2 or 3 installed, the INET "post" will not work. See the following microsoft KB articles:
FIX: Internet Transfer Control 5.0 "POST" Request Doesn't Work
http://support.microsoft.com/support/kb/articles/Q167/7/06.asp?LNG=ENG&SA=MSDN&FR=0
INFO: Visual Studio 97 Service Packs - What, Where, and Why
http://support.microsoft.com/support/kb/articles/Q170/3/65.ASP
INFO: Visual Basic 5.0 Fixes in Visual Studio 97 Service Pack 2
http://support.microsoft.com/support/kb/articles/Q171/5/54.asp?LNG=ENG&SA=MSDN&FR=0
Cheers!®©
ASKER
mcrider,
I'm at home and I don't have a copy of the script but the detail that saves the file, but it's basically something like:
use CGI;
$query= new CGI;
$fileup = $query->param('my_file');
# extract its name
$strFilename = $fileup;
$strFilename =~ s/.*\\([^\s\\]+)$/$1/;
# build a name for the file on the server
$localFile =~ s/\\[^\s\\]+$//;
$localFile .= "\path\" . $strFilename;
# save the file
open (OUTFILE,">$localFile");
binmode($fileup);
binmode(OUTFILE);
while ($bytesread=read($fileup,$
print OUTFILE $buffer;
}
I think the problem with the URLEncode function you posted is that it doen't encode the file and other parameters in a multipart format.
I've found it frustrating, and surprisingly dificult, trying to send and recieve a file over HTTP using VB and ASP (I couldn't get the posting acceptor to work, so I switched to perl). My background has more perl and it seems much esier to do things that way.
Thanks for the help so far, but I think vmv's approach might workout faster, any pointers on that method?
I'm at home and I don't have a copy of the script but the detail that saves the file, but it's basically something like:
use CGI;
$query= new CGI;
$fileup = $query->param('my_file');
# extract its name
$strFilename = $fileup;
$strFilename =~ s/.*\\([^\s\\]+)$/$1/;
# build a name for the file on the server
$localFile =~ s/\\[^\s\\]+$//;
$localFile .= "\path\" . $strFilename;
# save the file
open (OUTFILE,">$localFile");
binmode($fileup);
binmode(OUTFILE);
while ($bytesread=read($fileup,$
print OUTFILE $buffer;
}
I think the problem with the URLEncode function you posted is that it doen't encode the file and other parameters in a multipart format.
I've found it frustrating, and surprisingly dificult, trying to send and recieve a file over HTTP using VB and ASP (I couldn't get the posting acceptor to work, so I switched to perl). My background has more perl and it seems much esier to do things that way.
Thanks for the help so far, but I think vmv's approach might workout faster, any pointers on that method?
Have you read this from microsoft:
HOWTO: Use the PostData Parameter in WebBrowser Control
http://support.microsoft.com/support/kb/articles/Q174/9/23.ASP?LNG=ENG&SA=MSDN&FR=0
By the way, you never said... Are you using Service Pack 3??? If not, you will need to install it...
Cheers!®©
HOWTO: Use the PostData Parameter in WebBrowser Control
http://support.microsoft.com/support/kb/articles/Q174/9/23.ASP?LNG=ENG&SA=MSDN&FR=0
By the way, you never said... Are you using Service Pack 3??? If not, you will need to install it...
Cheers!®©
ASKER CERTIFIED SOLUTION
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ASKER
Hi mcrider,
Sorry it's been a while, well I've nearly got your answer working, I've found documentation on how to encode the file.
The only trouble is that the header parameter gets trashed between the Navagate method and the beforeNavagate2 event. Any ideas?
Thanks
Sorry it's been a while, well I've nearly got your answer working, I've found documentation on how to encode the file.
The only trouble is that the header parameter gets trashed between the Navagate method and the beforeNavagate2 event. Any ideas?
Thanks
What do you mean... "Gets trashed"?
ASKER
OK if my header for the navigate is "content-type: multipart/formdata; boundary=gc0p4Jq0M2Yt08j34
When I get to the beforeNavigate2 event the contents of the header reads something like "content-typcontent-type: multipart/formdata; boundary=gc0p4Jq0M2Yt08j34
the parameter is read only so I can't modify it. I'll double check the service pack status later.
When I get to the beforeNavigate2 event the contents of the header reads something like "content-typcontent-type: multipart/formdata; boundary=gc0p4Jq0M2Yt08j34
the parameter is read only so I can't modify it. I'll double check the service pack status later.
ASKER
Well I finally got it to work.
I've worked around the trashing of the headers by adding a string of spaces to the end of the header. (BTW I do have SP3 installed)
When sending a binary file you have to read it into a byte array and then convert it to unicode and store it in a string (it makes life a bit easier) build up the rest of the string and then convert it back from unicode and store it in a byte array.
I had a bit more trouble with the perl script at the other end but found that if I put in two boundaries in a row then it would see the attachment.
Thanks again.
Any way here is the code:
Private Sub post_Click()
Dim iHandle As Integer
Dim sFile As String
Dim sTemp As String
Dim sHeaders As String
Dim sBoundry As String
Dim sPost As String
Dim lSpot As Long
Dim lFind As Long
Dim bTemp() As Byte
sFile = "H:\1.jpg"
iHandle = FreeFile
Open sFile For Binary Access Read As iHandle
If iHandle Then
ReDim bTemp(LOF(iHandle)) As Byte
Get #iHandle, , bTemp
sTemp = StrConv(bTemp, vbUnicode)
Close iHandle
End If
sBoundry = "AaBbQQbBaA"
sHeaders = "Content-Type: multipart/form-data, boundry=" & sBoundry & _
vbCrLf & " "
sPost = "-----------" & sBoundry & vbCrLf & _
"-----------" & sBoundry & vbCrLf & _
"Content-Disposition: form-data; name=""my_file""; filename=""" & _
sFile & """" & vbCrLf & _
"Content-Type: image/jpg" & vbCrLf & _
"Content-Transfer-Encoding
vbCrLf & "-----------" & sBoundry & "--" & _
vbCrLf & "-----------" & sBoundry & "--" & vbCrLf
bTemp = StrConv(sPost, vbFromUnicode)
WB.Navigate "http://server3/postingwork/Finish.pl", navNoReadFromCache, "", bTemp, sHeaders
End Sub
I've worked around the trashing of the headers by adding a string of spaces to the end of the header. (BTW I do have SP3 installed)
When sending a binary file you have to read it into a byte array and then convert it to unicode and store it in a string (it makes life a bit easier) build up the rest of the string and then convert it back from unicode and store it in a byte array.
I had a bit more trouble with the perl script at the other end but found that if I put in two boundaries in a row then it would see the attachment.
Thanks again.
Any way here is the code:
Private Sub post_Click()
Dim iHandle As Integer
Dim sFile As String
Dim sTemp As String
Dim sHeaders As String
Dim sBoundry As String
Dim sPost As String
Dim lSpot As Long
Dim lFind As Long
Dim bTemp() As Byte
sFile = "H:\1.jpg"
iHandle = FreeFile
Open sFile For Binary Access Read As iHandle
If iHandle Then
ReDim bTemp(LOF(iHandle)) As Byte
Get #iHandle, , bTemp
sTemp = StrConv(bTemp, vbUnicode)
Close iHandle
End If
sBoundry = "AaBbQQbBaA"
sHeaders = "Content-Type: multipart/form-data, boundry=" & sBoundry & _
vbCrLf & " "
sPost = "-----------" & sBoundry & vbCrLf & _
"-----------" & sBoundry & vbCrLf & _
"Content-Disposition: form-data; name=""my_file""; filename=""" & _
sFile & """" & vbCrLf & _
"Content-Type: image/jpg" & vbCrLf & _
"Content-Transfer-Encoding
vbCrLf & "-----------" & sBoundry & "--" & _
vbCrLf & "-----------" & sBoundry & "--" & vbCrLf
bTemp = StrConv(sPost, vbFromUnicode)
WB.Navigate "http://server3/postingwork/Finish.pl", navNoReadFromCache, "", bTemp, sHeaders
End Sub
Thanks for the points! Glad I could help!
Cheers!®©
Cheers!®©
ASKER