Skip to main content

Method-Registration

Introduction​

Excel-DNA examines libraries specified in the .dna configuration file by Reflection, and registers appropriate methods with Excel using the xlfRegister C API call. The page describes the default registration processing, trouble-shooting and options for customization in the add-in.

Registration​

Default registration​

By default, Excel-DNA will attempt to register all 'public static' functions that have compatible signatures, for all the assemblies listed as <ExternalLibrary....> in your .dna file.

There are two optional attributes that you can put into the .dna file that control the registration:

ExplicitExports​

  • If you only want to register the functions explicitly marked with either an ExcelFunction or ExcelCommand attribute, you can add an ExplicitExports='true' tag in the .dna file:
    <ExternalLibrary Path="MyFunctions.dll" Pack="true" ExplicitExports="true" />
  • This attribute is valid in Project and ExternalLibrary tags in the .dna file.

ExplicitRegistration option​

If your add-in is going to do the registration explicitly (e.g. if you are using the Registration extension library) then you can add the ExplicitRegistration='true' tag in the .dna file. In this case Excel-DNA will not register any function automatically, and your add-in can do the registration by calling ExcelIntegration.RegisterDelegates(...).

The ExplicitRegistration option allows specific methods or libraries to opt out of the default registration processing. Such methods and libraries have to 'explicitly register' by calling one of the ExcelIntegration.RegisterXXX methods.

  • Valid on ExcelFunctionAttribute and ExcelCommandAttribute.

  • Valid in Project and ExternalLibrary tags in the .dna file.

  • When ExcelIntegration.RegisterMethods or ExcelIntegration.RegisterDelegates is called, the flag is removed from any attributes passed in before further processing.

Dynamic registration with ExcelIntegration.RegisterDelegates​

There is an Excel-DNA extension library that does custom method pre-processing and registration - see the ExcelDna.Registration project.

Registration Logging​

...