Minor success with Microsoft Excel XLSX files

Today, after much work, I had some success with Microsoft Excel and its XLSX format. For the first time, I successfully created an OOXML XLSX file that was acceptable to MS Excel.

I had tried this in September of last year. At the time, I had a file that could be read by OpenOffice but not by Microsoft Office.

Today I have a program that takes a plain text file, performs various manipulations, and produces a file that is usable by Microsoft Excel.

With this accomplishment, I now have libraries that can read and write spreadsheets for Lotus 1-2-3 and Excel. (OpenOffice is a possibility, but the client doesn't need that format. At least not yet.)

The work for OOXML was a different than the work for XLS format files. For the latter, I had documentation from Microsoft and a set of source code that produced the files. The work was mostly one of research and reading. For the XLSX files, the work was mostly reverse-engineering the OOXML files. Both approaches were helped by our test framework.