A brief introduction to Excel Macros

1. MACROS
CS1100 Computer Science and its Applications
CS1100 1

2. What is an Excel Macro?
• A macro is a set of instructions that tells Excel
to perform one or more actions
• An Excel macro is like a computer program but
it runs completely within Excel.
• Used to automate tedious or frequently
repeated tasks
– Macro can carry out sequence of actions much
more quickly

3. Macro Advantages
• Save time – even if you are an expert Excel
user, the computer can beat you every time
• Reduce errors – if the instructions are correct,
programs do not make mistakes
• Enforce standards – for example, each sales
rep may be required to submit a weekly
summary spreadsheet that follows a specific
structure and format

4. Macros
• Two ways to create a macro:
– Record it using the Macro Recorder
– Build by typing instructions in a VBA (Visual Basic
for Applications) module (beyond the scope of this
course)
– These two approaches can be combined

5. Macro Security
• Macro code can be used for evil too
• VBA macros included in Microsoft Office
documents (usually attached in emails) have
contained viruses in the past
– macro programs embedded in documents can be run
automatically when the document is opened, a
mechanism which can spread viruses.
• To configure security settings:
– File  Options  Excel Options  Trust Center
Trust Center Settings

6. Macro Viruses
• One famous macro virus called Melissa, released
in March, 1999:
– The virus sent a file called “List.doc” which it claimed
had passwords to 80 adult websites.
– Anyone who opened the document would get a free
copy of the Melissa macro virus.
– Melissa would then gather the first fifty entries in the
address book, and email itself to all of them.
– Melissa infected so many systems that by March 26th,
it was shutting down mail servers with all of the
infected emails traveling across the net.

7. Adding the Developer Tab
• Click on the File tab of the ribbon to open the File menu
• Click on Options to open the Excel Options dialog box.
• Click on the Customize Ribbon option in the left hand
window
• Under the Main Tabs section of the options window,
check off the Developer option.
• Click OK the Developer tab should now be visible

8. Workbook Formats
• The Excel default workbook format (.xlsx) does
not support macros
• To save a workbook containing macros, you
need to use one of the following formats:
– .xlsm
– .xlsb
– .xls

9. The Macro Recorder
• The recorder allows you to create macros
without knowing VBA
• Best to plan your macro before starting the
recorder
• If you’re curious about VBA and want to learn
to do more with macros, the recorder can be a
great learning tool
– You can examine the code that the recorder
generates and edit it.

10. The Macro Recorder dialog box
• 4 options to complete in this dialog box:
– Macro name - give your macro a descriptive
name. The name must begin with a letter and
have no spaces. Only letters, numbers and
underscore permitted.
– Shortcut key - (optional) fill in a letter, number,
or other character in the available space. This
will allow you to run the macro by holding down
the CTRL key and pressing the chosen letter on
the keyboard.
– Store macro in:
• This workbook: the macro is available only in this
file.
• New workbook: this option opens a new Excel file
and the macro is only available in the new file.
• Personal macro workbook: this creates a hidden file
Personal.xls which stores your macros and makes
them available in all Excel files
– Description: (optional) enter a description of
the macro

11. Macro Example
• Create a macro that automates the formatting
for a heading for the Atlantic Music Company:

12. Editing/Step Into a Macro
• An Excel macro is written in the Visual Basic
for Applications (VBA) programming language.
• Clicking on either the Edit or Step Into buttons
in the Macro dialog box starts the VBA editor
• Using the VBA editor and covering the VBA
programming language is beyond the scope of
this class.

13. Recording with Relative References
• By default a macro is recorded with absolute
references.
– If you are in Cell A1 when you record a macro, the
action will play back in A1
• To record with relative references,
click Use Relative References
• Now the macro plays
back in the selected cell.

14. Macro Example
• Let’s create a macro that automates the
format for a monthly sales summary: