public bool RegisterUserDefinedFunction( ExcelCalcFunction userDefinedFunction )
Users can build custom functions used in formulas by sub-classing the Infragistics.Documents.Excel.CalcEngine.ExcelCalcFunction class. Once the derived class is instantiated it must be registered by using the RegisterUserDefinedFunction method before being available and referenced by a formulas. Users can build a library of functions packaged in an assembly and register all the functions within the assembly by using the RegisterUserDefinedFunctionLibrary method.
Target Platforms: Android 4.4+, iOS 8+
Development Environments: Visual Studio 2015+, Visual Studio for Mac Preview, Xamarin for Visual Studio 4.2+