Download in Cache

  • Thread starter Thread starter NevilleT
  • Start date Start date
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NevilleT

I am trying to download a text file from a web site using the following code.

'--------------------------------------------
' Get the file from the Internet
If funIsNetConnected = True Then ' Check for an Internet
connection
lngRetVal = URLDownloadToFile(0, strTextFileURL, strLocalTextFile,
0, 0)
' Download the new file. If successful lngRetVal = 0
DoEvents
Else
GoTo Exit_subGetVersion ' No
Internet connection so exit.
End If

I am using a function (funIsNetConnected) to check for a connection to the
net.
strTextFileURL is the path to the file on the net. Once downloaded, the
text file contains the latest version and build number which I use to see if
there is an update to the program available.

The file seems to download without a problem however I am getting an old
version of the text file. In other words, if I change the text file on the
server, I still download the old version. I suspect somewhere it is being
cached, and rather than download the file, it is pulling a copy from a cache.
The speed at which the download occurs would confirm this. I have tried
deleting the file after I read it using

fso.DeleteFile (strLocalTextFile)

Has anyone had a similar experience with URLDownloadToFile and is there a
way to clear a cache before downloading?
 
NevilleT said:
I am trying to download a text file from a web site using the following
code.

'--------------------------------------------
' Get the file from the Internet
If funIsNetConnected = True Then ' Check for an Internet
connection
lngRetVal = URLDownloadToFile(0, strTextFileURL, strLocalTextFile,
0, 0)
' Download the new file. If successful lngRetVal = 0
DoEvents
Else
GoTo Exit_subGetVersion ' No
Internet connection so exit.
End If

I am using a function (funIsNetConnected) to check for a connection to the
net.
strTextFileURL is the path to the file on the net. Once downloaded, the
text file contains the latest version and build number which I use to see
if
there is an update to the program available.

The file seems to download without a problem however I am getting an old
version of the text file. In other words, if I change the text file on
the
server, I still download the old version. I suspect somewhere it is being
cached, and rather than download the file, it is pulling a copy from a
cache.
The speed at which the download occurs would confirm this. I have tried
deleting the file after I read it using

fso.DeleteFile (strLocalTextFile)

Has anyone had a similar experience with URLDownloadToFile and is there a
way to clear a cache before downloading?
Click to expand...


This link seems to address the caching problem with URLDownloadToFile:

http://vbnet.mvps.org/index.html?code/internet/urldownloadtofilenocache.htm
URLDownloadToFile: Fast, Simple and Transparent
File Downloads Bypassing the IE Cache

The code is for VB, not Access VBA, but should be easily adaptable.
 
Thanks Dirk. Just needed to include the DeleteUrlCacheEntry That fixed it.I
have a nice little version upgrade advice and automatic update function
working now. I must put it all together into a sample program others can
use. Thanks for your help.
 
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