Using ADO.Net and Com Interop to read, modify and output from Excel

Today I was asked to do what seemed like a fairly simple task: Take an Excel 2003 file, add a couple of columns of data and save to a new Excel file programattically. I haven't done any coding Excel for AGES so this i what I did. To read in the file and add the extra columm and data I did the following: Used OleDBConnection to grab the data from the sheet into a dataset Added some columns to the dataset did some processing and set the data in the dataset with the following code: