How to control how arguments display in Excel's function picker

Dec 28, 2013 at 5:44 PM

If you pick a function from the Formula tab function picker in Excel, it will show required arguments as bold and non required arguments normally. How can I attribute my UDF arguments to match that scheme? Currently, they are all showing up as bold, presumably because I used the ExcelArgument attribute on them.

Also, can I assign default values to optional parameters via attribution? If not, that would be a nice enhancement to the ExcelArgument attribute class.
Dec 28, 2013 at 9:17 PM
The Excel API gives us no way to indicate that some parameters are optional, so it's not possible for a user-defined function to affect the boldness in the Function Arguments dialog.

Dealing with optional and default arguments in the ExcelArgument attribute would be possible in a future version. For now my best plan is to follow the approach discussed here:

Marked as answer by j2associates on 12/28/2013 at 4:19 PM
Dec 28, 2013 at 11:16 PM
Thanks for the response, that is not a show stopper by any means. Earlier I saw this thread Optional Function Arguments in C#, which looks to be similar. If used inside a dna file, how do you reference it from other dna files? Does the dna file attribution tie things together in a roughly similar manner to .Net partial classes?