file size limit in Response.binarywrite

[S N]

I am using the following code to hide the download url of files on my website. The code uses Response.Binary write to send file to the client.
Kindly indicate the maximum size of the file that can be downloaded using this method.
I am hosting this site on a public server, so I will not be able to change anything on the webserver. Kindly indicate what can be done to ensure that the above method remains valid for any file size download.

call Response.AddHea der("Content-Disposition","a ttachment; filename=""" & strFileSave & """")
Response.Conten tType = "bad/type"
Set Fsys = Server.CreateOb ject("Scripting .FileSystemObje ct")
Set TS = Fsys.GetFile(st rFile).OpenAsTe xtStream(1, -1)
Do While Not (TS.AtEndOfStre am)
Response.Binary Write(TS.Read(1 ))
Loop

[=?Utf-8?B?T2xkIFBlZGFudA==?=]

RE: file size limit in Response.binary write

"S N" wrote:

I am using the following code to hide the download url of files on my website. The code uses Response.Binary write to send file to the client.
Kindly indicate the maximum size of the file that can be downloaded using this method.
call Response.AddHea der("Content-Disposition","a ttachment; filename=""" & strFileSave & """")
Response.Conten tType = "bad/type"
Set Fsys = Server.CreateOb ject("Scripting .FileSystemObje ct")
Set TS = Fsys.GetFile(st rFile).OpenAsTe xtStream(1, -1)
Do While Not (TS.AtEndOfStre am)
Response.Binary Write(TS.Read(1 ))
Loop

Ummm...that code isn't goint to work, anyway. See the method
OpenAsTEXTstrea m
???

You really can only use FileSystemObjec t reliably with text files; it wasn't
designed to work with binary files.

You need to use ADODB.Stream object, instead.

http://msdn.microsoft.com/en-us/library/ms675032(VS.85).aspx

And then you could easily control the amount you write in each chunk by just
limiting the amount you Read each time.

[S N]

Re: file size limit in Response.binary write

Thanks for the advice. I was under the impression that ADODB can be used
only for databases. This is the first instance of using it on files.
Can you please provide a sample code to hide download url by using ADODB
stream, while there should be no limit on the size of files to be
downloaded.

..
"Old Pedant" <OldPedant@disc ussions.microso ft.comwrote in message
news:C37071C4-3FB6-446F-BF6A-3755BFEC28BE@mi crosoft.com...

"S N" wrote:
>

>I am using the following code to hide the download url of files on my
>website. The code uses Response.Binary write to send file to the client.
>Kindly indicate the maximum size of the file that can be downloaded using
>this method.
>call Response.AddHea der("Content-Disposition","a ttachment; filename=""" &
>strFileSave & """")
> Response.Conten tType = "bad/type"
> Set Fsys = Server.CreateOb ject("Scripting .FileSystemObje ct")
> Set TS = Fsys.GetFile(st rFile).OpenAsTe xtStream(1, -1)
> Do While Not (TS.AtEndOfStre am)
> Response.Binary Write(TS.Read(1 ))
> Loop

>
Ummm...that code isn't goint to work, anyway. See the method
OpenAsTEXTstrea m
???
>
You really can only use FileSystemObjec t reliably with text files; it
wasn't
designed to work with binary files.
>
You need to use ADODB.Stream object, instead.

http://msdn.microsoft.com/en-us/library/ms675032(VS.85).aspx

>
And then you could easily control the amount you write in each chunk by
just
limiting the amount you Read each time.
>

[=?Utf-8?B?T2xkIFBlZGFudA==?=]

Re: file size limit in Response.binary write



"S N" wrote:

Can you please provide a sample code to hide download url by using ADODB
stream, while there should be no limit on the size of files to be
downloaded.

Good old Atrax has a couple of demos.

Note that his code is written in JScript for ASP, but conversion to VBScript
should be easy.

http://rtfm.atrax.co.uk/infinitemonkeys/articles/asp/934.asp

and

http://rtfm.atrax.co.uk/infinitemonkeys/articles/asp/935.asp

If you need more help, ask.

[S N]

Re: file size limit in Response.binary write

I would be grateful if you can give me vbscript code as well.
I would also like to clarify that the code for jscript forces save as
dialog. What if we want to hide the download url but dont want to force the
save as dialog, instead just want to see the pdf file within the browser
window itself.
Kindly advise on this.

Thanks in anticipation.

"Old Pedant" <OldPedant@disc ussions.microso ft.comwrote in message
news:03E3B997-93DE-4D4B-8C49-F5102BB39CEA@mi crosoft.com...

>
>
"S N" wrote:
>

>Can you please provide a sample code to hide download url by using ADODB
>stream, while there should be no limit on the size of files to be
>downloaded.

>
Good old Atrax has a couple of demos.
>
Note that his code is written in JScript for ASP, but conversion to
VBScript
should be easy.
>

http://rtfm.atrax.co.uk/infinitemonkeys/articles/asp/934.asp

and

http://rtfm.atrax.co.uk/infinitemonkeys/articles/asp/935.asp

>
If you need more help, ask.
>

[Anthony Jones]

Re: file size limit in Response.binary write


"S N" <uandme72@yahoo .comwrote in message
news:unVr3cOEJH A.4492@TK2MSFTN GP05.phx.gbl...

>I am using the following code to hide the download url of files on my
>website. The code uses Response.Binary write to send file to the >client.
>Kindly indicate the maximum size of the file that can be downloaded using
>this method.
>I am hosting this site on a public server, so I will not be able to change
>anything on the webserver. Kindly indicate what can be done to >ensure that
>the above method remains valid for any file size download.
>
>call Response.AddHea der("Content-Disposition","a ttachment; filename=""" &
>strFileSave & """")
Response.Conten tType = "bad/type"
Set Fsys = Server.CreateOb ject("Scripting .FileSystemObje ct")
Set TS = Fsys.GetFile(st rFile).OpenAsTe xtStream(1, -1)
Do While Not (TS.AtEndOfStre am)
Response.Binary Write(TS.Read(1 ))
Loop

Use this code:-

Sub SendFileToRespo nse(FilePath, FileName)

Const clChunkSize = 1048576 ' 1MB

Dim oStream, i
Response.Buffer = False

Response.Conten tType = "applicatio n/octet-stream"
Response.AddHea der "Content-Disposition", _
"attachment ; Filename=" & FileName

Set oStream = Server.CreateOb ject("ADODB.Str eam")
oStream.Type = 1 ' Binary
oStream.Open
oStream.LoadFro mFile FilePath

For i = 1 To oStream.Size \ clChunkSize
Response.Binary Write oStream.Read(cl ChunkSize)
Next
If (oStream.Size Mod clChunkSize) <0 Then
Response.Binary Write oStream.Read(oS tream.Size Mod clChunkSize)
End If
oStream.Close

End Sub

SendFileToRespo nse strFile, strFileSave

Note the Response.Buffer = false allows you to send a file of any size.

--
Anthony Jones - MVP ASP/ASP.NET

[S N]

Re: file size limit in Response.binary write

What if we want to use sendfiletorespo nse but dont want to force the save as
dialog, instead just want to see the pdf file within the browser window
itself.
is there any change required in the code to achieve this.

"Anthony Jones" <AnthonyWJones@ yadayadayada.co mwrote in message
news:e5fWrklEJH A.4092@TK2MSFTN GP06.phx.gbl...

>
"S N" <uandme72@yahoo .comwrote in message
news:unVr3cOEJH A.4492@TK2MSFTN GP05.phx.gbl...

>>I am using the following code to hide the download url of files on my
>>website. The code uses Response.Binary write to send file to the >client.
>>Kindly indicate the maximum size of the file that can be downloaded using
>>this method.
>>I am hosting this site on a public server, so I will not be able to change
>>anything on the webserver. Kindly indicate what can be done to >ensure
>>that the above method remains valid for any file size download.
>>
>>call Response.AddHea der("Content-Disposition","a ttachment; filename=""" &
>>strFileSave & """")
> Response.Conten tType = "bad/type"
> Set Fsys = Server.CreateOb ject("Scripting .FileSystemObje ct")
> Set TS = Fsys.GetFile(st rFile).OpenAsTe xtStream(1, -1)
> Do While Not (TS.AtEndOfStre am)
> Response.Binary Write(TS.Read(1 ))
> Loop

>
Use this code:-
>
Sub SendFileToRespo nse(FilePath, FileName)
>
Const clChunkSize = 1048576 ' 1MB
>
Dim oStream, i
Response.Buffer = False
>
Response.Conten tType = "applicatio n/octet-stream"
Response.AddHea der "Content-Disposition", _
"attachment ; Filename=" & FileName
>
Set oStream = Server.CreateOb ject("ADODB.Str eam")
oStream.Type = 1 ' Binary
oStream.Open
oStream.LoadFro mFile FilePath
>
For i = 1 To oStream.Size \ clChunkSize
Response.Binary Write oStream.Read(cl ChunkSize)
Next
If (oStream.Size Mod clChunkSize) <0 Then
Response.Binary Write oStream.Read(oS tream.Size Mod clChunkSize)
End If
oStream.Close
>
End Sub
>
SendFileToRespo nse strFile, strFileSave
>
Note the Response.Buffer = false allows you to send a file of any size.
>
--
Anthony Jones - MVP ASP/ASP.NET
>
>

[Anthony Jones]

Re: file size limit in Response.binary write

"S N" <uandme72@yahoo .comwrote in message
news:%23$Hxh7oE JHA.5448@TK2MSF TNGP04.phx.gbl. ..

What if we want to use sendfiletorespo nse but dont want to force the save
as dialog, instead just want to see the pdf file within the browser window
itself.
is there any change required in the code to achieve this.
>

If you know its a pdf then change content-type to application/pdf and remove
the attachment; keyword from content-disposition.

--
Anthony Jones - MVP ASP/ASP.NET

[S N]

Re: file size limit in Response.binary write

Following error received:

Response object error 'ASP 0157 : 80004005'
Buffering On

/test/dl.asp, line 2

Buffering cannot be turned off once it is already turned on.


Please note that I am hosting the site on a public server so there is no way
to ask the web admin to configure the server specifically for me. In such a
situation is it possible to eliminate the error as indicated above. Further,
if I am not able to switch off the response.buffer , will there be any
limitation on the size of file that i can download using
response.binary write?




"Anthony Jones" <AnthonyWJones@ yadayadayada.co mwrote in message
news:e94JHNpEJH A.5104@TK2MSFTN GP02.phx.gbl...

"S N" <uandme72@yahoo .comwrote in message
news:%23$Hxh7oE JHA.5448@TK2MSF TNGP04.phx.gbl. ..

>What if we want to use sendfiletorespo nse but dont want to force the save
>as dialog, instead just want to see the pdf file within the browser
>window itself.
>is there any change required in the code to achieve this.
>>

>
If you know its a pdf then change content-type to application/pdf and
remove the attachment; keyword from content-disposition.
>
--
Anthony Jones - MVP ASP/ASP.NET
>
>

[Anthony Jones]

Re: file size limit in Response.binary write

"S N" <uandme72@yahoo .comwrote in message
news:u4hyiirEJH A.4420@TK2MSFTN GP06.phx.gbl...

Following error received:
>
Response object error 'ASP 0157 : 80004005'
Buffering On
>
/test/dl.asp, line 2
>
Buffering cannot be turned off once it is already turned on.
>

You get this error if there is anything in your page or includes at the top
of the page which writes stuff to the response before your code has run.
Note any static content in the page will be sent.

Typical a page of this sort looks like:-

<!-- #include .... some common include -->
<%

' Code here that should note writing anything.
'My code I posted to you with your mods.
%>

Where the include is of a similar structure defininng constants and utility
functions.

>
Please note that I am hosting the site on a public server so there is no
way to ask the web admin to configure the server specifically for me.

Whilst an admin may have configured the buffer to be on (which is the
default) you can set it off as long as you do so before sending anything.

>In such a situation is it possible to eliminate the error as indicated
>above. Further, if I am not able to switch off the response.buffer , will
>there be any limitation on the size of file that i can download using
>response.binar ywrite?
>

Without turning it off there will be a limitation. The is a buffer size
limit that a public server administrator will almost certainly have
configured (the default on IIS6 is 4MB).

--
Anthony Jones - MVP ASP/ASP.NET

[S N]

Re: file size limit in Response.binary write

Also advise the content type in case the file is an excel file, word
document, exe file, zip file etc.

Thanks in advance.


"Anthony Jones" <AnthonyWJones@ yadayadayada.co mwrote in message
news:e94JHNpEJH A.5104@TK2MSFTN GP02.phx.gbl...

"S N" <uandme72@yahoo .comwrote in message
news:%23$Hxh7oE JHA.5448@TK2MSF TNGP04.phx.gbl. ..

>What if we want to use sendfiletorespo nse but dont want to force the save
>as dialog, instead just want to see the pdf file within the browser
>window itself.
>is there any change required in the code to achieve this.
>>

>
If you know its a pdf then change content-type to application/pdf and
remove the attachment; keyword from content-disposition.
>
--
Anthony Jones - MVP ASP/ASP.NET
>
>

[=?Utf-8?B?T2xkIFBlZGFudA==?=]

Re: file size limit in Response.binary write



"S N" wrote:

Just one clarification
You intended
For i = 1 To oStream.Size / clChunkSize
or
For i = 1 To oStream.Size \ clChunkSize

He *intended* the latter.

The backslash operator means "integer division" in VBScript (and VB and
VB.NET) code.

That is,
a \ b
is equivalent to
INT( a / b )

*************** *****

Also, you don't need to mess with Response.Buffer =False, at all.

Just follow each
Response.Binary Write
with
Response.Flush

Now the buffer will never get more full than one "chunkSize" .

[Anthony Jones]

Re: file size limit in Response.binary write

"Old Pedant" <OldPedant@disc ussions.microso ft.comwrote in message
news:85265E45-E160-4DE4-A613-E47DF74D5AD7@mi crosoft.com...

>
>
"S N" wrote:
>

>Just one clarification
>You intended
> For i = 1 To oStream.Size / clChunkSize
>or
> For i = 1 To oStream.Size \ clChunkSize

>
He *intended* the latter.
>
The backslash operator means "integer division" in VBScript (and VB and
VB.NET) code.
>
That is,
a \ b
is equivalent to
INT( a / b )
>
*************** *****
>
Also, you don't need to mess with Response.Buffer =False, at all.
>
Just follow each
Response.Binary Write
with
Response.Flush
>
Now the buffer will never get more full than one "chunkSize" .
>

Yes that would work. However it would mask unintended errors that turning
the buffer off right at the top of the code exposes.

--
Anthony Jones - MVP ASP/ASP.NET

[S N]

Re: file size limit in Response.binary write


"Anthony Jones" <AnthonyWJones@ yadayadayada.co mwrote in message
news:usmtyA4EJH A.1268@TK2MSFTN GP05.phx.gbl...

"Old Pedant" <OldPedant@disc ussions.microso ft.comwrote in message
news:85265E45-E160-4DE4-A613-E47DF74D5AD7@mi crosoft.com...

>>
>>
>"S N" wrote:
>>

>>Just one clarification
>>You intended
>> For i = 1 To oStream.Size / clChunkSize
>>or
>> For i = 1 To oStream.Size \ clChunkSize

>>
>He *intended* the latter.
>>
>The backslash operator means "integer division" in VBScript (and VB and
>VB.NET) code.
>>
>That is,
> a \ b
>is equivalent to
> INT( a / b )
>>
>************** ******
>>
>Also, you don't need to mess with Response.Buffer =False, at all.
>>
>Just follow each
> Response.Binary Write
>with
> Response.Flush
>>
>Now the buffer will never get more full than one "chunkSize" .
>>

>
Yes that would work. However it would mask unintended errors that turning
the buffer off right at the top of the code exposes.
>
--
Anthony Jones - MVP ASP/ASP.NET
>
>

what kind of errors would be exposed by turning off the buffer. kindly
elaborate.

[Anthony Jones]

Re: file size limit in Response.binary write

"S N" <uandme72@yahoo .comwrote in message
news:OYWSgZaFJH A.912@TK2MSFTNG P02.phx.gbl...

>
"Anthony Jones" <AnthonyWJones@ yadayadayada.co mwrote in message
news:usmtyA4EJH A.1268@TK2MSFTN GP05.phx.gbl...

>"Old Pedant" <OldPedant@disc ussions.microso ft.comwrote in message
>news:85265E4 5-E160-4DE4-A613-E47DF74D5AD7@mi crosoft.com...

>>>
>>>
>>"S N" wrote:
>>>
>>>Just one clarification
>>>You intended
>>> For i = 1 To oStream.Size / clChunkSize
>>>or
>>> For i = 1 To oStream.Size \ clChunkSize
>>>
>>He *intended* the latter.
>>>
>>The backslash operator means "integer division" in VBScript (and VB and
>>VB.NET) code.
>>>
>>That is,
>> a \ b
>>is equivalent to
>> INT( a / b )
>>>
>>************* *******
>>>
>>Also, you don't need to mess with Response.Buffer =False, at all.
>>>
>>Just follow each
>> Response.Binary Write
>>with
>> Response.Flush
>>>
>>Now the buffer will never get more full than one "chunkSize" .
>>>

>>
>Yes that would work. However it would mask unintended errors that
>turning the buffer off right at the top of the code exposes.
>>
>>

>
>
>
what kind of errors would be exposed by turning off the buffer. kindly
elaborate.
>

Well the sort of problems you've discovered where you may unintentionaly be
placing things in the output buffer that you didn't want present. Example:-

<!-- #include /virtual="/someinclude.asp " -->
<%
Response.Conten tType = "applicatio n/octet-stream"
Do Until ....
Response.Binary Write SomeStuff
Response.Flush
Loop
%>

'someinclude.as p

<!-- Ooops some accidental static content here -->
<%

'utility code

%>

Placing a Response.Buffer at the top of your page would barf immediately on
that line alerting you to a problem.
It also saves you having to remember to Response.Flush if you have multiple
places where you write to the buffer.

--
Anthony Jones - MVP ASP/ASP.NET