Visual Basic for Applications (VBA)
• An object-oriented programming language
– Instructions for the manipulation of objects
– A structured way to provide instructions to
Excel
• Excel has an Object Library that defines its
set of objects (e.g. workbooks, charts,
ranges of cells)
Logic of Language
• First part of a command identifies the object
• Second part of command:
– Sets a property of the object (e.g. color or font)
– Takes an action on the object (e.g.copy or
move)
– Sets an attribute to the object (e.g. assigns a
value to it using := )
Example of an Instruction
• Application.Workbooks(“Book1.xls”).Work
sheets(“Sheet1”).Range(“A1”).Font.Name=
“Arial”
• Application.Workbooks(“Book1.xls”).Work
sheets(“Sheet1”).Range(“A1”) is the object
• Font.Name=“Arial” is the property being
set
Control of VBA
• A Procedure is a set of instructions that
operate on a set of objects
• A Function is a procedure that returns a
value as a result
• A Subroutine is a procedure that can be run
or used by another macro
VBA Toolbar (Excel 2003)
Developer Tab (Excel 2007)
BlueCell Macro
Sub bluecell()
'
' bluecell Macro
'
With Selection.Interior
.Pattern = xlSolid
.PatternColorIndex = xlAutomatic
.Color = 16777062
.TintAndShade = 0
.PatternTintAndShade = 0
End With
End Sub
Running Macros
•
•
•
•
Run Macro option
Shortcut Keys: [Ctrl][Shift] letter
Command Buttons
Custom Toolbar
Running Solver through a Macro
• Solver dialog box must have been opened at least
once in current Excel session (i.e. Solver must be
currently activated in Excel)
• SolverSolve UserFinish:=True
• Tools Reference option in VBA must have Solver
selected
• Other VBA commands for controlling Solver in
class handout
Debugging VBA Code
• When VBA encounters a problem, it will
highlight line in yellow.
• Use [f8] key to step through code
• Use the Reset icon button (square) at top of
VBA to exit step-through mode and troubleshoot code or Excel/VBA settings. Cannot
retry macro until yellow highlight is gone.
Plotting the Efficient Frontier –
Version 1A Command Button
Private Sub EfficientFrontier_Click()
Range("C53") = Range("B59")
SolverSolve UserFinish:=True
Range("D59") = Range("C51")
End Sub
Plotting the Efficient Frontier –
Version 1B Command Button
Private Sub EfficientFrontier_Click()
For unit = 1 To 11
Range("C53") = Range("B" & 58 + unit)
SolverSolve UserFinish:=True
Range("D" & 58 + unit) = Range("C51")
Next unit
End Sub