Visual Basic for Applications (VBA) for Excel

1. Visual Basic for Applications (VBA)for Excel Prof. Yitzchak Rosenthal

2. Start the Visual Basic Editor • Microsoft office applications (e.g. Excel , powerpoint, word, access) have a built-in visual basic editor • Choose menu choice "Tools | Macro | Visual Basic Editor"

3. The Visual Basic Editor

4. Separate Windows VB Editor Window Spreadsheet Window The VB editor is opened in a separate window from the Excel spreadsheet. If you close the VB editor you can continue using the spreadsheet. IF YOU CLOSE THE SPREADSHEET, THE VB EDITOR WILL CLOSE

5. Separate Code Sections • There are different code sections. • Double click on a sheet or workbook to enter code for that sheet or workbook. Step1: Double click here. Step2: Enter code for sheet1

6. Insert | Module • Choose the “insert | module”menu to create a new module. • Modules contain generic code that is used by any sheet.

7. Recording Macros

8. Tools | Macro | Record New Macro • Choose the menu choice “Tools | Macro | Record New Macro” to start the macro recorder.

9. Enter a name • Enter a name for the Macro and press OK

10. Stop Recording Button • When you start recording a macro, the “Stop Recording” Toolbar displays. • Press the “stop recording” button when you are finished performing the steps for the macro. “Stop Recording” Button

11. Perform the Steps for the Macro in Excel • Perform whatever actions you want in Excel. • Example: • Step 1: insert a new line at the top of the spreadsheet. • Step 2: click on cell A1 to select it • Then press “stop recording”. • See next slide for the VBA code that is created by the macro recorder.

12. See code in VB Editor Look at the “Modules” in the VB Editor to see the code for the recorded macro.

13. Execute the Macro • To execute the macro, choose the menu choice, “Tools | Macro | Macros”

14. Run the Macro Then choose the macro and click “Run”.

15. The Macro is Executed See the new row

16. VBA vsVB.Net

17. VBA vs VB.Net • You can use manyVB.Net concepts and code in VBA • Like VB.Net, VBA also provides the ability to create textboxes, buttons, checkboxes, radio buttons, etc. for use in Excel (we will not cover how to do that here). HOWEVER • VBA is based on an older version of Visual Basic. • There are some differences between how to write VBA and VB.Net code.

18. MsgBox vs MessageBox.Show • MsgBox vs MessageBox.show • VBA: MsgBox ("Hello There") • VB.Net: MessageBox.Show("Hello There")

19. No HANDLES clause in VBA • Event Handlers • VBA • No "Handles" clause. • Name of sub determines which event is handled • Example Private Sub Button1_Click() MsgBox ("hello there") End Sub • VB.Net • Needs "Handles" clause • Name of sub does NOT determine which event is handled • Example Private Sub Button1_Click( ByVal sender As System.Object, _ ByVal e As System.EventArgs) _ Handles Button1.Click MessageBox.Show("Hello there") End Sub

20. DIM may not use initialization value • VB.Net • In VB.Net you can declare a variable with Dim and give it an initial value all in one step.Dim number as Integer = 1 • VBA • In VBA you MAY NOT use an initialization value in a Dim statement. • Therefore the code above would not be legal. • Instead do the following:Dim number as Integernumber = 1

21. Call • Calling a Sub • VBA: • Must use the "Call" keyword if sub is in a different module • Don't use parentheses if the sub doesn't contain any parameters • Example: Call DoIt • VB.Net: • Just use the name of the Sub • Example: DoIt( )

22. Writing Your Own Code

23. Sub • Place all code to be executed in a "subroutine" • Will explain more soon ... Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub

24. How to run (i.e. execute) a sub • To execute the subroutine: • first :place cursor anywhere in the Sub • second :Choose menu choice:Run | Run Macro Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub

25. Other ways to execute a sub • To execute the subroutine: • first :place cursor anywhere in the Sub • second :Press F5 OR press the "Run macro" button Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub

26. What happens when you run this subroutine?

27. Running the subroutine • Excel spreadsheet displays • First message box appears. • Press OK • Second Message box appears • Press OK • subroutine is finished (returns to the code window) Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub When you press OK the 2nd message box will appear (not shown)

28. Functions

29. Functions • You can define your own VBA functions for use in the Excel spreadsheet.

30. Sample Function This function calculates the sum of the values from lowNumber to highNumber Function summation(lowNumber As Integer, highNumber As Integer) as Integer Dim count As Integer summation = 0 For count = lowNumber To highNumber summation = summation + count Next count End Function

31. Using the sample function in Excel Formulas View ValuesView

32. Rules for Functions • The function has a type specified AFTER the parameter list • Function summation(lowNumber As Integer, highNumber As Integer) as Integer • The name of the function is used as a variable inside the function • The entire function call “becomes the value” that the name of the function had when the function finished executing.

33. Quick Intro to VB for the Novice

34. Syntax • Syntax • syntax means the "grammar" of (or the rules for writing) a programming language or command

35. Syntax of SUB These are required • First line : • Must type "Sub" (without the quotes) • make up a name for the sub • must type parentheses • Body : • Use VBA statements • Last Line: • must type "End Sub" (without the quotes) VBA statements go here make up a name for the Sub (more later ...) Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub

36. More than one sub • You can have many Subroutines • Each subroutine must have a unique name • When you execute a subroutine only it runs, not the other subroutines

37. Example Sub doSomething ( ) MsgBox ("Hello There") MsgBox ("How are you doing?") End Sub Sub doSomethingElse ( ) MsgBox ("I am having fun.") MsgBox ("Are you having fun?") End Sub • Each sub has a unique name • You can run each sub separately

38. Rules for subroutine names • Rules for Subroutine names • must start with a letter • can include • letters (e.g. A B C a b c etc.) • digits (e.g. 0 1 2 etc.) • underscores (i.e. _ ) • may not be a VBA "keyword" • some keywords are "sub", "end", "dim" (we'll see more later) • may NOT include any "special" characters (e.g. !@# etc) • Examples on next slide ...

39. Examples • Legal subroutine names • mySubroutine • hello • born2ride • born_to_ride • Illegal subroutine names • 3cheers • may not start with a number • bagels&lox • may not include characters other than letters or nubmers or underscore ( _ ) • name with spaces • may not include spaces in the name

40. END OF PRESENTATION The following slides are “in progress”

41. MsgBox ("Your message goes here")

42. MsgBox( ) • MsgBox ( ) is used to display a dialog box with a message to the user. • Syntax: • You must include the word "MsgBox" (without the quotes) followed by a set of parentheses • Place the message in the parentheses • For now (until I teach you otherwise) assume that the entire message should be enclosed in quotes (later we'll learn more about when you don't need the quotes ...) • For now (until I teach you otherwise) assume that the entire statement must be typed on one line (later we'll learn how to break up a long line ...) • Example on next slide ...

43. Example • Sub showAMessageBox( )MsgBox ("This will be displayed in a message box")End Sub Put the message in quotes.

44. Numbers • If your message only includes a number, you do NOT have to put it in quotes (we'll explain why later) • Example: The following is perfectly fine:Sub showANumber( ) MsgBox(123)End Sub No quotes necessary around a number.

45. Expressions

46. Only one "value"

47. String Expression • String expressions"This is a constant string expression""This is another string expression" • Numeric expressions33+4

48. msgbox(<string expression>)

49. Differences between VB.Net and VBA

50. MsgBox vs MessageBox.Show VB.Net: MessageBox.Show(“my message”) VBA: msgbox(“my message”)