Convert from an excel or csv file into a fixed-length record text file.

We need a Windows application which shows a quick preview of an excel or csv file (sample attached) so the user can open that file, assign the columns to a list of pre-defined output fields and generate a fixed record length text file. The input fields would be: Product Code, Barcode, Description, Price and Date. The columns in each input file can be in different order and formats (with or without thousands separators, comma or period decimal character...) but the resulting file should always be in the predefined format. The conversion process would be: the user will pick a file, then assign the columns, and get the converted file, one at a time. It must run from WindowsXP to Win 10 (32-bit). Ideally written in c# but vb.net (even vb6) would be acceptable. Source code needed.