Hi there,

For one of our clients I am writing the technical and functional specs for 
the following situation:

1. The client has a catalog of products inside a database. The content for 
each product can be written to an HTML file.
2. These HTML files together with some linked Images are put on CD to form 
a simple HTML based catalog.
3. Currently, users of our client can browse this catalog by simply opening 
the index page from CD in their browser, because all other pages are linked 
from there.

Now, one of the requirements for the new project is that the files on CD 
should be updateble through the internet. The file should be downloaded and 
saved at the client, so even off-line the catalog is still up to date.

Here is what I think that should be done:

1. Have a client VB application connect to the site, check for updates and 
download any new file which it saves on the hard drive
2. The normal internet browser can no longer be used, because it has to 
look on both the CD as on the hard drive. Therefore, a very simple custom 
browser can be build in VB. This browser checks the hard disk for a certain 
file, and if it isn't there, it assumes it's on the CD.

In my opinion, this shouldn't be too hard. But here is what I would like to 
know:

1. Did somebody ever try something like this before? If so, how did you 
handle version conflicts? How did you force the app to look at disk AND CD-Rom?
2. What method did you / can I use to "stamp" a file to a certain version? 
A naming scheme? Or did you map product names to filenames in some sort of 
lookup file? What would be the best approach for something like this?
3. How did you / can I keep track of different versions of the file?
4. What is the best way to retrieve images that are in the source of the 
HTML? I personally think of a list of all available images as comments in 
the HTML file. That can easily be parsed, after which the individual images 
can be downloaded. (This may be more of an implementation issue, but I 
think it will also influence (database) design now.)

In the current situation, it looks like the programmers assigned to this 
project handle VB better than other languages, so I think I am stuck to 
that. (No problem with that, though).
What would be the best approach to handle something like this in VB? I am 
aware of the existence of controls like the Inet Control, the Webbrowser 
control and various (third party) FTP controls. What would be the best option?

As I am only writing the specs at the moment, currently some conceptual 
thoughts on this are more welcome than raw code.


I am sorry if this is a bit long-winded, but I felt it was important to 
explain the specs in some depth.

Thanks in advance for any insights on this subject.

Imar