VSTO Excel Add-In and SpreadsheetGear
We're working on a Excel Add-In in C# .Net 4. One of the requirements is to update a worksheet with results of some processing. The issue is, we need to do this both while the Excel file is open (with the Add-In), and also in batch (while the file is closed).
We have a SpreadsheetGear licence already to generate Excel files. Is it possible to modify an XLS file whilst it is open in Excel, using SpreadsheetGear? Or must we have two sets of code to generate the same information? One using Excel Interop for open files, and one using SpreadsheetGear on closed files?
Got a direct response from SpreadsheetGear.
SpreadsheetGear runs on a totally separate process from Excel and has no way to access their runtime and/or currently opened workbooks—our product was built from the ground up using the .NET Framework libraries and has absolutely no dependencies from Excel. The only way to access files like you require would be to first save them to disk from Excel and then open them with SpreadsheetGear.
So it looks as if we'll have to implement two sets of code to do the same thing.