VBA Programming

Part One

Our Dartmouth Legacy10 INPUT "What is your name: "; U$

20 PRINT "Hello "; U$

25 REM

30 INPUT "How many stars do you want: "; N

35 S$ = ""

40 FOR I = 1 TO N

50 S$ = S$ + "*"

55 NEXT I

60 PRINT S$

65 REM

Startup Excel and hit…

Alt-F11

First things first: Getting Help

Getting More Help

Project Explorer

• Excel objects

• User Forms

• Code Modules

Properties Window

Properties are an object's characteristics, e.g. a sheet's name.

Immediate Window

Using the Immediate Window

Try the Immediate Window MsgBox("Hello!") x = 1 + 1 debug.Print x 'this is a comment x = WorksheetFunction.Sum(1,2) debug.Print x

Insert a module

Add some codeSub HelloWorld() MyName = InputBox("What is your name?") MsgBox ("Hi " + MyName)End Sub

Type "HelloWorld" in the Immediate Window to run your program.

Go back to Excel and run it from the Tools|Macro menu

Subroutines vs. Functions Both are procedures: A named sequence

of statements executed as a unit. (MS) Functions return a value Subroutines don't

Procedures take arguments

Arguments are variables

But what are variables? "A named storage location that can

contain data that can be modified during program execution." (MS)

1. Has name2. Contains data3. Can be modified

Convert Celsius to Fahrenheit

Function Fahrenheit(Celsius) Fahrenheit = (Celsius * 1.8) + 32End Function

Use the Function

Back to the Immediate Windowx = 1debug.Print x 1 x = 2debug.Print x 2

'Set the value of x to 1

'Now set it to 2

Making Decisions

Decisions: If…ThenFunction VeryHot(Celsius) If (Celsius > 30) Then VeryHot = True Else VeryHot = False End IfEnd Function

Which number is bigger?Function MyMax(x, y) If ( … ) Then … Else … End IfEnd Function

Remember: 'FunctionName = Result'

Which number is bigger? (Solution)Function MyMax(x, y) If ( x > y ) Then MyMax = x Else MyMax = y End IfEnd Function

Loops: For…NextFor Variable = BeginValue to EndValue

do something with VariableNext

Sub firstLoop() For x = 1 To 10 Debug.Print x NextEnd Sub

Example: Sum of 1…N

Function SumToN(N) SumToN = 0 For x = 1 To N SumToN = SumToN + x NextEnd Function

TemperatureChart Create a sub called TemperatureChart Use For…Next to loop Celsius from 0 to 40 Use debug.print to output the result of

converting Celsius to Fahrenheit using our function

TemperatureChart (Solution)

Sub TemperatureChart() For Celsius = 0 To 40 Debug.Print Fahrenheit(Celsius) NextEnd Sub

What we have covered so far… The VBA environment Inserting a module Running a macro Writing a user-defined function Using the new function in Excel Variables If…Then…Else For…Next