 Excel – Basic Elements  Using Macros  Excel VBA Basics  Excel VBA Advanced

 Module – collection of logically related procedures grouped together  Procedure – a group of ordered statements enclosed by Sub and End Sub  Function – the same as a procedure, but also returns some value and is closed between Function and End Function key words

Sub ShowTime() Range("C1") = Now() End Sub Function sumNo(x, y) sumNo = x + y End Function The procedure places the current time inside cell C1 The function returns sum of two input numbers, whose values are in the parameter variables x & y

Sub z(a) MsgBox a End Sub Sub x() Call z("ABC") End Sub Sub y() z "ABC “ End Sub Sub ShowSum() MsgBox _ Module1.sumNo(3,5) End Sub Function sumNo(x, y) sumNo = x + y End Function If there are few sumNo functions, the full name of the function is needed

 Passing arguments by reference –  Is the VBA default  Means, if any changes happened to the argument variables, they will be preserved after the function/procedure finishes  Passing arguments by value –  Is possible in VBA (by explicit definition)  Means, the pre-calling state of the argument variables will be preserved after the procedure/function finishes

Sub TestPassing1() Dim y As Integer y = 50 AddNo1 y MsgBox y AddNo2 y MsgBox y End Sub Sub AddNo1(ByRef x As Integer) x = x + 10 End Sub Sub AddNo2(x As Integer) x = x + 10 End Sub public Sub TestPassing2() Dim y As Integer y = 50 AddNo3 y MsgBox y End Sub private Sub AddNo3(ByVal x _ As Integer) x = x + 10 End Sub

 Use public to allow any module to call the function/procedure  Use private to make limited access to the function/procedure (only from the owning module)

 A variable is used to store temporary information within a Procedure, Module …  A variable name  Must start with letter and can ’ t contain spaces and special characters (such as “ & ”, “ % ”, “ \ ” )  Can ’ t be any excel keyword ( “ if ”, “ while ”… )  Can ’ t have identical name to any existing class ( “ Wroksheet ”, “ Workbook ”… )

 Byte – positive integer numbers (0:255)  Integer – integers (-32,768 : 32,767)  Long – 4-byte integer  Currency – for fixed-point calculations  Single – 2-byte floating-point numbers

 Double – double-precision floating-point numbers  Date – used to store dates and times as real numbers.  String – contains a sequence of characters

Sub NoVariable() Range("A1").Value = _ Range("B2").Value Range("A2").Value = _ Range("B2").Value * 2 Range("A3").Value = _ Range("B2").Value * 4 Range("B2").Value = _ Range("B2").Value * 5 End Sub Sub WithVariable() Dim _ iValue as Integer iValue = _ Range("B2").Value Range("A1").Value = _ iValue Range("A2").Value = _ iValue * 2 Range("A3").Value = _ iValue * 4 Range("B2").Value = _ iValue * 5 End Sub In VB the end of statement is in the end of line. To write the same statement in few lines use “ _ ” at the end of line!

 Declaring Variables  Format: Dim varibaleName AS dataType  Examples:  Dim myText As String  Dim myNum As Integer  Dim myObj As Range  The default value of  any numeric variable is zero  any string variable – “” (empty string)  an Object variable – is nothing (still the declaration will store space for the object!!!)

 In VB you don ’ t have to declare variable before its usage  Then, VB will by itself declare such variable as “ Variant ”  You can also declare variable as “ Variant ”  Dim myVar as Variant  Variant – means that the variable may contain any data type  The price is very high!!! – any time VB access such variable, it will spend time on “ deciding ” what is its “ current ” type!

 To assign a value to a Numeric or String type Variable, you simply use your Variable name, followed by the equals sign (=) and then the String or Numeric  To assign an Object to an Object type variable you must use the key word "Set"

Sub ParseValue() Dim sWord as String Dim iNumber as Integer Dim rCell as Range Set rCell = Range("A1") sWord = Range("A1").Text iNumber = Range("A1").Value End Sub

 The scope & lifecycle of a variable defines the code where the variable can be accessed and time when the stored data is kept inside the variable  Procedure-Level  Variables defined inside procedures  Can be accessed only inside the procedure and keep their data until the End statement of the procedure  Module-Level  Defined in the top of a Module  Any procedure inside the Module can access the variable  The variable retains the values unless the Workbook closes  Project-Level, Workbook Level, or Public Module-Level  Defined as “ Public ” in the top of a Module  Can be accesses by any procedure in any module  The variable retains the values unless the Workbook closes

 Sub scopeExample() Dim x as Integer x = 5 End Sub  Dim y as Integer ‘ all the module procedures are here …  Public z as Integer ‘ all the module procedures are here … Procedure level variables Module level variables Project level variables

 Workbook: the class represents an Excel file  Worksheet: represents a single worksheet  Sheet: represents a single worksheet or chartsheet  Cell: represents a single cell

A current Worksheet A Range C4:D7 A Cell A Current Workbook

 Workbooks: a collection of objects of class “ Workbook ”  Worksheets: a collection of objects of class “ Worksheet ”  Sheets: a collection of Sheet objects  Range: a range of objects of class Cell

Sub Test1() Worksheets("Sheet1").Range("A10", "B12") = "Hello “ Worksheets(1).Range("A13,B14") = "World!" End Sub This will take the whole square between the two cells The range of two cells Two equal ways to refer Sheet1

Which Workbook was Used?

Sub ShowWorkSheets() Dim mySheet As Worksheet For Each mySheet In Worksheets MsgBox mySheet.Name Next mySheet End Sub

How many times the user will click on the button?

 Cells indexing format:  Cells(row, column), where both row and column are given as integers (starting from 1)  Cells(index) – see the next slide  Following expressions are equivalent and refer to the cell A1 in the currently active sheet:  ActiveSheet.Range.Cells(1,1)  Range.Cells(1,1)  Cells(1,1)

Range( “ B1:F5 ” ).Cells(12) = “ XYZ ” See how we calculate cell 12 In the given range!

ActiveCell.Offset(4, 5) = 1 This is the currently active cell The assignment result

 Workbooks.Close – closes the active workbook  Workbooks.Count – returns the number of currently open workbooks  Range( “ A1 ” ) is the same as Range( “ A1 ” ).Value  Worksheets(1).Column( “ A:B ” ).AutoFit  Worksheets(1).Range( “ A1:A10 ” ).Sort_  Workbooks.Open fileName:= “ Hello.xls ”, password:= “ kukuriku ”

Dim myRange as Range Set myRange = Range( “ A1:A10 ” )

 Suppose, we want to keep a collection of all the books that we loan,  Or we want to keep lists of tasks for all the days of the week  The na ï ve solution is to keep a lot of variables  Another solution is to create array keeping the whole collection together

Dim LoanBooks(3) LoanBooks(1) = “ Winnie The Pooh ” LoanBooks(2) = “ Adventures of Huckleberry Finn ” LoanBook(3) = “ Frankenstein ” The array declaration. The size must be defined here!

Dim WeekTasks(7,2) WeekTasks(1,1) = “ To buy milk ” WeekTasks(7,1) = “ To dance ” … MsgBox WeekTasks(1,1) & ” ” & WeekTasks(1,2) _ & vbCrLf & WeekTasks(2,1) … What will the code print?

 There are two ways to resize the existing array:  ReDim LoanBooks(7) – will erase the old values  ReDim Preserve LoanBooks(7) – will preserve values in indexes 1-3

 Dim A(1 To 100, 0 To 3, -3 To 4)  UBound(A, 1) – will return “ 100 ”  UBound(A, 2) – will return “ 3 ”  UBound(A, 3) – will return “ 4 ”  LBound(A, 1) – will return “ 1 ”  LBound(A, 2) – will return “ 0 ”  LBound(A, 3) – will return “ -3 ”  Write code calculating the size of each one of the sub-arrays

 If Age >= 18 Then Status = "Adult" End If  If Age >=18 Then Status = “ Adult ” Vote = “ Yes ” Else Status = “ Child ” Vote = “ No ” End If

 If Age >= 18 Then MsgBox "You can vote" ElseIf Age >=22 and Age < 62 Then MsgBox “ You can drive ” End If

 Select Case Grade Case Is >= 90 LetterGrade = "A" Case Is >= 80 LetterGrade = "B" Case Is >= 70 LetterGrade = "C" Case Is >= 60 LetterGrade = "D" Case Else LetterGrade = “ E" End Select

For i = 10 to 1 Step -2 Cells(i, 1) = “ AB ” Next i i = 1 Do While i =< 10 Cells(i, 1) = i i = i + 1 Loop i = 1 Do Cells(i, 1) = i i = i + 1 Loop While i < 11

Sub CellsExample() For i = 1 To 5 For j = 1 To 5 Cells(i, j) = "Row " & i & " Col " & j Next j Next i End Sub