Using XLL+ 6.2, you can import entire .NET assemblies, and XLL+ will automatically generate add-in functions for any methods or properties that you select.

You can use Attributes in your .NET code to indicate which methods and properties you want to export, and to add any special treatment for functions or their arguments.

Alternatively, you can use the XLL+ Import Editor to select the exported methods, without changing your existing .NET code in any way.

See Importing .NET assemblies in the User Guide for more details.