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VBA in Excel

Walter Milner

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Introduction

• VBA = Visual Basic for Applications• Enables end-user programming• In MS Office applications• Formulae and macros OK for simple actions,

but..• Advantages over formulae and macros:

– Multiple nested if is easy– Loops easy– Debugging easy

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Getting started

View..Toolbars..Control

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Add a button

Click the button buttonDrag on sheet to create one

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Format it

Right click on buttonSelect propertiesSet as requiredNote distinction between name and caption

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Program it

Right click buttonSelect View code:

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Test it

On Control Toolbox, click set squareThis toggles run/designClick the button

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Referring to cells

Private Sub CommandButton1_Click()Dim x As IntegerDim y As IntegerDim z As IntegerDim result As Integerx = Cells(1, 2).Valuey = Cells(2, 2).Valuez = Cells(3, 2).Valueresult = x * y + zCells(4, 2).Value = resultEnd Sub

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The VBA Excel Object model

• Hierarchy of classes• Use to refer to things

in an Excel application• Very large number of

classes, properties and methods

• Have to use on-screen help for reference

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The VBA Excel Object model

• Object is a thing• Property is some

property of an object• Method is something

the object can be told to do

• Event is something that can happen to the object

• Collection is a set of related objects

• Enumeration is action returning complete set of things (eg all fonts on system)

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Example object - Application

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Example properties of Application

Program a button which sets a value for this property and see what happens

Try it in a loop for a bizarre effect

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Example method

Program a button which calls the findfile method of the application

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Example collection -

Display the count property of the worksheets collection in a msgbox to show how many sheets there are in the workbook

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Using For Each .. Next in a collection

Private Sub CommandButton4_Click()Dim w As WorksheetFor Each w In Application.Worksheets MsgBox (w.Name)NextEnd Sub

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The RangeSelection property of the ActiveWindow

This is a Range objectSo it has the properties of a Range objectUse them to program a button which displays the totalof the numbers in the cells selected

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2d array exercise

Use the RangeSelection property to program a button which does a vertical flip of selected cells