What is VBA - · PDF fileExcel VBA Terminologies The two main types of Procedures are Sub...

What is VBA

VBA stands for Visual Basic for

Applications an event driven

programming language from Microsoft

that is now predominantly used with

Microsoft office applications such as

MS-Excel, MS-Word and MS-Access.

THINGS WE WILL COVER

In this Short Tutorial we will cover the

basics such as

How to Enable Developer Menu and

Accessing VBA Editor

Excel VBA Terminologies

Using VBA Loops

Using Range and Cells Object

Workbook and Worksheet Object

How to Enable Developer Menu

and Accessing VBA Editor

Accessing VBA Editor

In Excel window, press "ALT+F11". VBA

window opens as shown below.



First enable 'Developer' menu in Excel 20XX. To do the same, click on

File >> Options.

Step 2. Click Customize Ribbon Tab and check 'Developer' and click 'OK'.



The 'Developer' ribbon appears in menu

bar.



Now We can add as many Controls

such as Command Buttons and other

Controls as well

Excel VBA Terminologies

The two main types of Procedures are Sub and Function.

Function

A function is a group of reusable code which can be called anywhere in your program. This eliminates the need of writing same code over and over again. This will enable programmers to divide a big program into a number of small and manageable functions.

Apart from inbuilt Functions, VBA allows us to write user-defined functions as well and statements are written between Function and End Function

Sub Procedures

Sub Procedures work similar to functions while Sub procedures DONOT Return a value while functions may or may not return a value. Sub procedures Can be called without call keyword. Sub procedures are always enclosed within Sub and End Sub statements.

Using VBA Loops

‘For Loop

Private Sub CommandButton1_Click()

'For Loop

Dim a As Integer

a = 10

For i = 0 To a - 1 Step 1

MsgBox "The Value of i is " & i

Next

End Sub

‘For Each Loop


fruits = Array("Apple", "Orange", "Cherry", "Grape")

Dim fruitName As Variant

For Each Item In fruits

fruitName = "FruitName is " & Item

MsgBox fruitName

Next

End Sub

Using VBA Loops

'While Wend Loop


Dim Counter As Integer

Counter = 10

While Counter < 16

Counter = Counter + 1

MsgBox "Value of Counter is " & Counter

Wend

End Sub

'Do While Loop


Dim i As Integer

Do While i < 5

i = i + 1

MsgBox "The Value of i is" & i

Loop

End Sub

Using VBA Loops

‘Exit For Loop Private Sub CommandButton5_Click()

Dim i As Integer

i = 10

For k = 0 To i - 1 Step 1

MsgBox ("The Value of k is " & k)

If k = 4 Then

k = k * i

MsgBox ("Maximum Value Reached. k = " & k)

Exit For

End If

Next

End Sub

'Do Until Loop Private Sub CommandButton6_Click()

Dim i As Integer

i = 10

Do Until i > 15

i = i + 1

MsgBox ("The Value of i is " & i)

Loop

End Sub

Using Range Object

The Range object, which is the representation of

a cell (or cells) on your worksheet, is the most

important object of Excel VBA.

For Example:

Range("A1:A4").Value = 5

Range("A1:A2,B3:C4").Value = 10

Using Cells Object

Instead of Range, you can also use Cells. Using

Cells is particularly useful when you want to loop

through ranges.

For Example:

Cells(3, 2).Value = 2

Range(Cells(1, 1), Cells(4, 1)).Value = 5

http://www.excel-easy.com/vba/loop.html

Programming with Range and Cells

Dim example As Range Set example = Range("A1:C4") example.Value = 8

Select

An important method of the Range object is the Select method. The Select method simply selects a range.

Dim example As Range Set example = Range("A1:C4") example.Select


Rows and Columns Property

The Rows property gives access to a specific row of a range

The Columns property gives access to a specific column of a range.

Dim example As Range

Set example = Range("A1:C4")

example.Rows(3).Select

example.Columns(2).Select


Copy/Paste

The Copy and Paste method are used to copy a range and to paste it

somewhere else on the worksheet.

Range("A1:A2").Select

Selection.Copy

Range("C3").Select

ActiveSheet.Paste


Clear

To clear the content of an Excel range, you can use the

ClearContents method.

Range("A1").ClearContents / Range("A1").Value = "“

Count

Dim example As Range

Set example = Range("A1:C4")

MsgBox example.Rows.Count


The mother of all objects is Excel itself. We call it the Application object.

The application object contains other objects. For example, the

Workbook object (Excel file). This can be any workbook you have

created. The Workbook object contains other objects, such as the

Worksheet object. The Worksheet object contains other objects, such

as the Range object.

For Example:

Range("A1").Value = "Hello“

but what we really meant was:

Application.Workbooks(“Workbook-

Name").Worksheets(1).Range("A1").Value = "Hello"

You can refer to a member of the collection, for example, a

single Worksheet object, in three ways.

Using the worksheet name.

Worksheets("Sales").Range("A1").Value = "Hello“

Using the index number (1 is the first worksheet starting from

the left).

Worksheets(1).Range("A1").Value = "Hello”

Using the CodeName

Sheet1.Range("A1").Value = "Hello"


Properties and Methods

The Add method of the Workbooks collection creates a new

workbook.

Workbooks.Add

The Count property of the Worksheets collection counts the

number of worksheets in a workbook.

MsgBox Worksheets.Count

Result when you click the command button on the sheet:


For Loop in Excel Macros

Single Loop

Dim i As Integer For i = 1 To 6 Cells(i, 1).Value = 100 Next I

Double Loop

Dim i As Integer, j As Integer For i = 1 To 6 For j = 1 To 2 Cells(i, j).Value = 100 Next j Next i

Triple Loop

Dim c As Integer, i As Integer, j As Integer For c = 1 To 3 For i = 1 To 6 For j = 1 To 2 Worksheets(c).Cells(i, j).Value = 100 Next j Next i Next c

Besides the For Next loop, there are other loops as I have

conveyed earlier in Excel VBA. For example, the Do While

Loop. Code placed between Do While and Loop will be repeated

as long as the part after Do While is true.

Dim i As Integer

i = 1

Do While i < 6

Cells(i, 1).Value = 20

i = i + 1

Loop

Dim i As Integer

i = 1

Do While Cells(i, 1).Value <> ""

Cells(i, 2).Value = Cells(i, 1).Value + 10

i = i + 1

Loop

Do While in Excel Macros

Data Types Excel VBA data types can be grossly divided into two types, the

numeric data types and non-numeric data types. They are

classified below:

Numeric Data Types

Numeric data types are types of data that consist of numbers,

which can be computed mathematically with various standard

arithmetic operators such as add, minus, multiply, divide and so

on. In Excel VBA, the numeric data are divided into 7 types, which

are summarized in below table.

Non-numeric Data Types

The nonnumeric data types are summarized below:

Data Types

Data Type Storage Range

String(fixed length) Length of string 1 to 65,400 characters

String(variable length) Length + 10 bytes 0 to 2 billion characters

Date 8 bytes January 1, 100 to December 31,

9999

Boolean 2 bytes True or False

Object 4 bytes Any embedded object

Variant(numeric) 16 bytes Any value as large as Double

Variant(text) Length+22 bytes Same as variable-length string

Implicit Declaration

MyFirstName=“Sunayan"

MyAge=32

Excel VBA automatically create two variables MyFirstName and

MyAge as variants, and they are assigned data as Sunayan and 32

respectively. This type of declaration is called implicit declaration.

Explicit Declaration

Here Variables are normally declared in the general section of the

codes window using the Dim statement.

The syntax is as follows:

Dim variableName as DataType

Dim yourName As String

Dim firstnum As Integer

Dim BirthDay As Date

Data Types

Declaring Arrays in Excel VBA We use the Dim statement to declare an array just as the way we declare a single variable. In Excel VBA, we can have a one dimensional array, two dimensional array or even a multidimensional array (up to 60)

One Dimensional Array

The general statements to declare a one dimensional array in Excel VBA is as follows:

Dim arrayName(index) as dataType or

Dim arrayName(first index to last index) as dataType

For example,

Dim StudentName(10) as String

Dim StudentName(1 to 10) as String

Dim StudentMark(10) as Single

Dim StudentMark( 1 to 10) as Single

Example Private Sub CommandButton1_Click()

Dim StudentName(1 to 5) As String

For i = 1 To 5

StudentName(i) = InputBox("Enter student Name")

Cells(i, 1) = StudentName(i)

Next

End Sub

Declaring Arrays in Excel VBA

Private Sub CommandButton1_Click( )

Dim StudentName(3) As String, StudentID(3) As String,

StudentMark(3) As Single

For i = 1 To 3

StudentName(i) = InputBox("Enter student Name")

StudentID(i) = InputBox("Enter student ID")

StudentMark(i) = InputBox("Enter student Mark")

Cells(i, 1) = StudentName(i)

Cells(i, 2) = StudentID(i)

Cells(i, 3) = StudentMark(i)

Next

End Sub


Two Dimensional Array

The format to declare a two dimensional array is

Dim arrayName (num1, num2) as datatype

Dim Score (3, 3) as Integer

will create a two dimension array consists of 16 elements. These elements can be organized in a table form as shown in the table below

If you set the option base to 1, then there will be only 9 elements, i.e. from Score(1,1) to Score(3,3). However, if you want the first element to start with suffixes (1,1) you can also use the following format of declaration:

Dim Score(1 to 3, 1 to 3) as Integer


Score(0,0) Score(0,1) Score(0,2) Score(0,3)




There are three kind of operators.

Arithmetic Operators

Comparison Operators

Logical Operators

Arithmetic Operator

Operators

Operator Mathematical function Example

^ Exponential MsgBox 2^4 gives a value of 16

* Multiplication MsgBox 4*3 gives a value of 12,

/ Division MsgBox 12/4 gives a value of 3

Mod

Modulus (returns the

remainder from an integer

division)

MsgBox 15 Mod 4 gives value of 3

\ Integer Division(discards

the decimal places) MsgBox 19\4 gives a value of 4

+ or & String concatenation

MsgBox "Excel"&"VBA 2010" or

"Excel"+"VBA 2010" produces a new

string "Excel VBA 2010"

Comparison Operators

Operators

Operator Meaning Example

< Less than

MsgBox 2<3 returns

true while MsgBox 4>5

returns false

<= Less than or equal to MsgBox 3<=4 returns

true

> Greater than MsgBox 5>4 returns

true

>= Greater than or equal to MsgBox 10>=9 returns

true

= Equal to MsgBox 10=10 returns

true

<> Not Equal to MsgBox 9<>10 returns

true

Logical Operators

Logical operators are also used in writing decision making

codes by comparing values or expressions.

Operators

Operator Meaning Example

And Logical Conjunction If A>=80 And B<101

thenGrade="A"

Or Logical Disjunction If income>5000 or car>2

thenStatus="Rich"

Not Logical negation MsgBox Not (3 >

4)returns true

Xor

Similar to Or, except

that it returns False if

both camparison values

are true

MsgBox 4 > 3 Xor 5 >2

returns false

Function and Sub

A function is a group of reusable code which can be called anywhere in your program. This eliminates the need of writing same code over and over again. This will enable programmers to divide a big program into a number of small and manageable functions.

Apart from inbuilt Functions, VBA allows us to write user-defined functions as well. Below Code will explain you how to write your own functions in VBA.

Function findArea(Length As Double, Optional Width As Variant)

If IsMissing(Width) Then

findArea = Length * Length

Else

findArea = Length * Width

End If

End Function

The Output of the area would be displayed to the user.

Function and Sub Sub Procedures

Sub Procedures are similar to functions but there are few differences.

Sub procedures DONOT Return a value while functions may or may not return a value.

Sub procedures Can be called without call keyword.

Sub procedures are always enclosed within Sub and End Sub statements.

Sub Area(x As Double, y As Double)

MsgBox x * y

End Sub

Function and Sub

Calling Procedures :

To invoke a Procedure somewhere in the script, you can

make a call from a function. We will not be able to use the

same way as that of a function as sub-procedure WILL NOT

return a value.

Function findArea(Length As Double, Width As Variant)

area Length, Width ' To Calculate Area 'area' sub proc is called

End Function

Sub Area(x As Double, y As Double)

MsgBox x * y

End Sub

There are three types of errors in programming:

Syntax Errors

Runtime Errors

Logical Errors.

Syntax errors, also called parsing errors, occur at interpretation

time for VBScript.

For Example: Function ErrorHanlding_Demo()

dim x,y x = "Tutorialspoint"

y = Ucase(x

End Function

The following line causes a syntax error because it is missing a closing

parenthesis.

Error/Exception Handling


Runtime errors

Runtime errors, also called exceptions, occur during execution, after interpretation.

For example, the following line causes a runtime error because here syntax is correct but at runtime it is trying to call fnmultiply, which is a non-existing function:

------------------------------------------------ Function ErrorHanlding_Demo1()

Dim x,y

x = 10

y = 20

z = fnadd(x,y)

a = fnmultiply(x,y)

End Function

------------------------------------------------------

Function fnadd(x,y)

fnadd = x+y

End Function

Error/Exception Handling Logical errors

Logic errors can be the most difficult type of errors to track

down. These errors are not the result of a syntax or runtime

error. Instead, they occur when you make a mistake in the

logic that drives your script and you do not get the result you

expected.

For example, dividing a number by zero or a script that is written

which enters into infinite loop.

Err Object

Assume if we have a runtime error, then the execution stops by

displaying the error message. As a developer, if we want to

capture the error, then Error Object is used.

Err.Number gives the error number and Err.Description

gives error description.


Public Sub OnErrorDemo()

On Error GoTo ErrorHandler ' Enable error-handling routine.

Dim x, y, z As Integer

x = 50

y = 0

z = x / y ' Divide by ZERO Error Raises

ErrorHandler: ' Error-handling routine.

Select Case Err.Number ' Evaluate error number.

Case 10 ' Divide by zero error

MsgBox ("You attempted to divide by zero!")

Case Else

MsgBox "UNKNOWN ERROR - Error# " & Err.Number & " : " & Err.Description

End Select

Resume Next

End Sub

Assignment

1. There is an Excel Sheet in the Following Workbook named "Assignment.xlsx"

2. You don't know the Count of rows or columns

3. You will have to create a button clicking upon which all the data should move to a new sheet with a message box saying relevant message

4. You have to save the newly created worksheet.

Userform Programming Open the Visual Basic

Editor. If the Project

Explorer is not visible,

click View, Project

Explorer.

Click Insert,

Userform. If the

Toolbox does not

appear

automatically, click

View, Toolbox. Your

screen should be

set up as below.

http://www.excel-easy.com/vba/create-a-macro.html

http://www.excel-easy.com/vba/create-a-macro.html

Userform Programming

.

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