I'm writing a application which converts data from an excel file into an XML file for another application. You make some changes to the excel file, save them, load them in my C# forms application as readonly and then save the resultant xml. Only problem is, this is a very iterative process and at the moment my application throws an exception if the file is open in excel. So to get it to work, you have to shut down excel (or close file), run application, then reopen excel.
My code is this;
using (var stream = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.Read))
which causes a IO Exception.