C# – Password Protecting an Excel file in C#


Does anyone know the syntax for this? I've been looking everywhere and all I can find is C++ code for this. I'm trying to password protect an excel file programatically using the System.IO.Packaging namespace.

Any ideas?

Additional notes:

I'm NOT using the Excel interop–but instead the System.IO.Packaging namespace to encrypt and password protect the excel file.

Best Solution

If you want an Excel password all you need is something like this:

using Microsoft.Office.Interop.Excel

//create your spreadsheet here...

WorkbookObject.Password = password;

This requires Excel to be installed.

That's nothing to do with System.IO.Packaging of course, so you might need to restate your question...