KSpread (part of KOffice) reads/writes Excel files. KSpread uses Qt (and KDE libs).

Have you checked to see how they do it?

xsacha wrote:

KSpread (part of KOffice) reads/writes Excel files. KSpread uses Qt (and KDE libs).

Have you checked to see how they do it?

Watch out re the licensing on this app!!!

Do you really need Excel output, or do you just need to output data that Excel can read?

If the latter is enough, considder a simpler format like csv. Otherwise, you may want to investigate either the .ods or the .xlsx format. Both are packed structures with XML files, but they are not simple I have heard. I never worked with them directly.

A last option that may be workable is to go through ODBC and QtSql. You can read and write Excel files that way, but of course there are limits to what you can do there.

Hi,
you could of course also look at the new XML-based formats.

I’ve found some infos on the Excel 2003 XML format on this page [blogs.msdn.com]. Could be a good start.

CSV ist not an option, it’s very cumbersome to read and write correctly. And the users receiving the CSV must take care of the correct settings (charset, delimiter, enclosing quotes and all that). That’s error prone and the support for it is a nightmare – we all are developers, aren’t we? :-) Also we need it in both directions (import Excel sheets of our users into our database and generate spread sheets for the users filled with our data).

Unfortunately we also must support opening Excel files in the native (i.e. non-XML) format, otherwise we would had to convert them by hand. Giving xlsx to our users would be ok.

Forgive me for the stupid idea, but this has worked well at Tamoggemon’s in the past.

Why not create a server with a Qt -> VBA -> Excel -> Qt bridge. If the user wants to open an excel file, it gets sent to the server, converted there and sent home to him…

We can have Jexcelapi on the server using java. No problem with that. This way we have to put everything to the server, but I want do do some things in the Qt/C++ based client.

Volker wrote:

Unfortunately we also must support opening Excel files in the native (i.e. non-XML) format, otherwise we would had to convert them by hand. Giving xlsx to our users would be ok.

I believe Microsoft has a tool for converting non-XML to XML. You may be able to use it in a batch process.

So you only need to get info out? You don’t need to be able to edit it and save it? There are quite a number of tools to convert XML files in to other formats, I believe.

You did read of that “platform independent” thingy, didn’t you? :) To be able to work on a Mac I cannot use the Microsoft tools. And of course that tool exists, it’s called Excel :)

I think it’s a downloadable tool for people with old versions of Excel actually. Standalone. But yes, it was a Windows app.

You have Excel on Mac [ehow.co.uk] too :P

There may be a Mac app for this. Or you could try wine (or similar).

Probably make life much easier.

Come on… you cannot force your commercial customers to install wine just to convert some crappy xls files :-)

Everthing other than a lib I can incorporate to my app is not acceptable; it’s more pleasent for the user if we upload the files to the business logic server then.

Alright, I guess since it is for paying customers it is best to treat them nice.

Good luck with your Excel API. I’m sure someone has written something like it for Qt somewhere. You checked Qt-Apps already and similar sites?

This can search Excel files: http://qt-apps.org/content/show.php/recoll?content=66138
But might not have the full API.

I’ve searched around with google, got some things that might be interesting, but nothing with using Qt in the first search results. It’s not on a very high priority at the moment, so no need to worry. I thought it’s worth a try in this forum – if you don’t ask, you won’t get an answer…

There are 2 C++ libaries to create excel.
One is free xlslib : http://xlslib.sourceforge.net/
Other is commercial libXL : http://www.libxl.com/

Sorry for late response and I don’t know whether you need this or not. But for others I share…

Thanks for the links. libxl I will have a look into. xlslib unfortunately cannot read XLS files. This is the crucial part. Writing the files could be quite easily approached with the new XML based format (thats seems not too complicated as long as there are no formulas or cross references, which we do not need).