Question

I have to compare two Excel files having different number of sheets, different number of columns/rows, merged cells, formulas etc.

The output of the comparison should allow the user to see which rows/columns were added, deleted, modified, re-arranged. This whole thing has to be done using C#,.NET

Can anyone help me out?

Answer 1

You need to define your scope better. As @Brijeesh suggested, there are 3rd party libraries like EPPLus, and also NPOI for reading the files. But this is not about reading the files, but rather performing some “comparison” that you have an idea in your head how you want it to happen.

This question is too broad to be answered in a single thread like this.

• Are the spreadsheets in a known format?
• Do you only want to check certain sheets / columns ?
• You mentioned wanting to see which columns were re-arranged, this implies knowing what order they were in the first place. Again – is the spreadsheet in a known format?

You should start to answer these questions, and trim down the scope of what you’re trying to do into manageable tasks.

EDIT:

VSTO has its benefits, and it’s downfalls (the user must have excel installed). 3rd party libraries also have their ups and downs. Which method you should use for accessing the spreadsheets was not the question in this thread.

Again – focus on one thing at a time. What do you want to compare, and how do you want to do it? Then you can worry about which library you should use. Though – when you’re ready to ask that question, open a separate question so that the posts can stay on topic.