Microsoft Office Tutorials and References
In Depth Information
Lesson 22: Add-Ins
Add-ins are a useful feature in Excel, considered by many Excel developers to be an
indispensable tool when distributing their custom projects to a wider audience. Anyone can create an
add-in — it’s the kind of thing that’s easy to do once you know how. This lesson discusses the
concept of add-ins and how to incorporate them into your Excel projects.
This lesson discusses standard Excel add-ins. Two other types of add-ins exist that
are not developed with VBA and are not discussed in this lesson. One of the other
types is called COM add-ins, developed with languages such as Visual Basic, C++,
and J++ that support Component Object Model components. The other type is
DLL add-ins, which are Windows files known as Dynamic Link Library files.
WHAT is An ExcEl Add-in?
An Excel add-in is a special type of Excel workbook that has been converted to an add-in file.
There is no magic to the add-in conversion process, but after you create an add-in file, you’ll
notice its unique characteristics:
The file extension is .xla for Excel versions prior to 2007, and .xlam for Excel versions
2007 and 2010.
Add-ins are always hidden; you do not open and view them as you would an Excel
You cannot show sheets of any kind belonging to the add-in file.
The add-in file is not recognized as an open workbook in the Workbooks collection.