Tag: openxml


Considerations for storing Excel cell value in code

You may hate Excel, but you may find a discussion of how Excel stores cell values interesting. So I have a spreadsheet library. The biggest concern at the initial stage was how to store all the spreadsheet data efficiently. I hear people talking about millions of cells, so I’m scared. If my program stores a […]


Calculate Excel column width pixel interval

Brace yourself. You’re about to learn the secret behind how Excel mysteriously calculates the column width intervals. In this article, I’m not going into the details of the column widths, but the column width intervals. There’s a difference. From the Open XML SDK specs: width = Truncate([{Number of Characters} * {Maximum Digit Width} + {5 […]


How to properly use OpenXmlWriter to write large Excel files

Brian Jones already wrote something on using the OpenXmlWriter with the Open XML SDK to write large Excel files. There are a couple of things that weren’t mentioned though. OpenXmlWriter works best for creating new things For the purposes of explanation, we’ll assume the “new thing” is a new worksheet, although OpenXmlWriter can be used […]


How to create an Open XML spreadsheet bar chart

Today, you’re going to learn how to insert a bar chart into an Open XML spreadsheet. Frankly speaking, the basics apply to the other types of charts, so if you master this, you can figure out how to create the other charts. First, download the source code and the resulting Excel file. I’m not going […]


Future of spreadsheets

So I was checking some site statistics for my spreadsheet library website and I found an interesting search phrase: “open xml excel future”. The person might have been checking how important spreadsheets are in the future. Or maybe just checking if Microsoft Excel is still around. Spreadsheets are still going to be used in future. […]


OSBC Launch

My Open XML spreadsheet course is up! Click here for details. So here’s an interesting tidbit. Writing lesson 3 (recognising styles) was the most tedious part for me. It was unbearably boring for me. It was all I could do to slog through writing each word, coming up with screenshots and writing up example source […]


Teaching classes

I’ve been asked what possible career could I have with a maths degree. The asker usually already have an answer. Be a teacher. When I graduated from university, it was about a year after Sep 9/11. Finding a job was hard. My friends, driven to desperation, decided to see if teaching was a viable career. […]


Open XML SDK class structure

I’ve gotten a few questions on the class structure of the Open XML SDK. There are articles on Open XML itself, where you work directly with XML files and tags, and zip them up yourself. Basically you work with WordprocessingML (Word), SpreadsheetML (Excel), PresentationML (PowerPoint) and possibly DrawingML (for images and stuff). Eric White did […]