Excel 2010 Bible

903

CHAPTER

Creating Custom

Excel Add-Ins

IN THIS CHAPTER

Understanding add-ins

Converting a workbook to

an add-in

F

or developers, one of the most useful features in Excel is the capability

to create add-ins. This chapter discusses this concept and provides a

practical example of creating an add-in.

What Is an Add-In?

Generally speaking, an add-in is something that’s added to software to give it

additional functionality. Excel includes several add-ins, including the

Analysis ToolPak and Solver. Ideally, the new features blend in well with the

original interface so that they appear to be part of the program.

Excel’s approach to add-ins is quite powerful because any knowledgeable

Excel user can create add-ins from workbooks. An Excel add-in is basically a

different form of a workbook file. Any Excel workbook can be converted

into an add-in, but not every workbook is a good candidate for an add-in.

What distinguishes an add-in form a normal workbook? Add-ins, by default,
have an .xlam extension In addition, add-ins are always hidden, so you
can’t display worksheets or chart sheets that are contained in an add-in. But,
you can access its VBA procedures and display dialog boxes that are con-
tained on UserForms.