An add-in is essentially a workbook file with a few important differences:
♦ The workbook's IsAddin property is True — which means that it can be loaded by choosing the Tools ^ Add-Ins command.
♦ The workbook is hidden and cannot be unhidden by the user. Consequently, an add-in is never the active workbook.
♦ When using VBA, the workbook is not part of the Workbooks collection.
Many add-ins provide new features or functions to Excel. You can access these new features as if they were built into the product.
You can create your own add-ins from XLS workbook files. In fact, creating add-ins is the preferred method of distributing some types of Excel applications. Add-ins have an XLA extension by default, but you can use any extension that you like.
Besides XLA add-ins, Excel supports XLL add-ins and (beginning with Excel 2000) COM add-ins.These types of add-ins are created using software other than Excel.This book discusses only XLA add-ins.
Chapter 21 covers the topic of add-ins in detail.
Was this article helpful?