Visual Basic 6.0

1CopyrightMr.Anjan Mahanta LCCTInternational Studies Program
INTRODUCTION TO
Visual Basic 6.0
Instructor: Anjan Mahanta
GUI Programming
2201-2412

Course Outline
 Introduction to VB
 Analyzing VB Programs
 Controls & Properties
 Examining Labels, Buttons & Text Boxes
 Putting Code into Visual Basic
 Message & Input Boxes
 Making Decisions
 VB Looping
 List Boxes & Data Lists
 Additional Controls
 Modular Programming
 Built-In Functions
 VB Database Basics
 Menus & VB
 The Graphics Image Controls
 Toolbars & More Graphics
 Database Connectivity & Programming

Introduction to Visual Basic 6.0
 What is Visual Basic?
Creates Graphic User Interface (GUI)
Creates applications for the Microsoft Windows OS
Major components:
1. Forms
2. Controls
3. Commands
4. Objects

History of Visual Basic
• Alan Cooper developed Visual Basic in 1988 and
sold to Microsoft
• VB1 Debuts at Windows World in March 20,1991
• VB2 Debuts in November 1992
• VB3 Debuts in June 1993
• VB4 Debuts in October 1996
• VB5 Debuts in April 1997
• VB6 Debuts in October 1998

 What programming language is Visual Basic
based on?
BASIC (stands for Beginner’s All Purpose
Symbolic Introduction Code)

Starting Visual Basic 6.0
• Click on Start
• Select Programs
• Select Microsoft Visual Studio 6.0
• Click on Microsoft Visual Basic 6.0
• Click on Open

Visual Basic 6.0 Programming Window

 What is a Form Window?
The form window holds the application’s
form background and all its user controls,
such as command buttons.
 What is a Toolbox?
The toolbox contains the controls that you
place on the Form Window. All the controls
appear on the toolbox.

Creating Your First Application
• Design your form as below:
Text
BoxCommand Button
Command Button
Label
Text Box

Writing the program
• Double click on the command button ADD

• Enter the following code
Label5= val(text1) + val(text2)
To display answer Number 2
Number 1
Value
Writing the program

• Enter number 1 (any number)
• Enter number 2 (any number)
Click on ADD
Running the program

• Click on ADD Command button
Running the program

Calculator

Controls in the Toolbox
• Label
– A label control is used to display text that a user can’t
change directly.
• Textbox
– A textbox control is used to input data from the user at run
time.
• Command button
– A command button is used to perform an event at run time.

Addition of three numbers

Area of a Triangle

Code
• Double click on AREA
• Type,
Private Sub Command2_Click()
Text 3 = 0.5 * val(Text1) * Val(Text2)
End Sub

Area of Circle

Code
• Double click on AREA
• Type,
Text2 = 3.14 * (Val(Text1) ^2)
End Sub

Discount

Code
• Double click on Discount
• Type,
Text3 = Val (Text1) * (Val(text2) / 100)
End Sub

Code
• Double click on Total
• Type,
Text4 = Val(Text1) - Val(Text3)
End Sub

Exercise

IF …..Then…..Else
Statement
• If...Then...Else statement is used for
controlling the program flow.
• To control the VB program flow, we
can use various conditional operators
and logical operators.

Conditional Operators
Operator Meaning
= Equal to
> Greater than
< Less Than
< > Not Equal to
• The conditional operators compares data
values and then decide what action to take.

Examples
A=10, B=15
Operations Result
Is A=B ?
FALSE / NO
Is A>B ?
FALSE / NO
Is A<B ?
TRUE / YES
Is A< >B ?
TRUE / YES

Logical Operators
AND: Both sides must be true
Side A Side B Result
TRUE TRUE ?
TRUE
TRUE FALSE ?
FALSE

Logical Operators
OR: One side or other must be true
Side A Side B Result
TRUE TRUE ?
TRUE
FALSE TRUE ?
TRUE
FALSE FALSE ?
FALSE

The general format for the if...then...else statement is
If conditions Then
VB expressions
Else
VB expressions
End If

Program for next class..
Design Mode
Text Box
Command Button

Run Mode
• When the program is Run, if the
user enters value greater than 8.

Run Mode
• When the program is Run, if the
user enters value less than 8.

Coding..
• Double Click on OK
If Text1 > 8 Then
MsgBox (“You are late !!”)
Else
MsgBox (“You are not late !!”)
End If
End Sub

Form Color
Option1 Option3 Option5
Option2 Option4 Option6

Code
• Double click on Option1
Private Sub Option1_Click()
If Option1.Enabled = True Then
Form1.BackColor = vbRed
End If
End Sub

Code
Form1.BackColor = vbBlue
End If
End Sub

Code
Form1.BackColor = vbWhite
End If
End Sub

Code
Form1.BackColor = vbBlack
End If
End Sub

Code
Form1.BackColor = vbYellow
End If
End Sub

Code
Form1.BackColor = vbGreen
End If
End Sub

Form Font
Label1
Option 2
Option 3
Option 4
Option 5
Option 6
Option 1

Code
Label1.FontBold = True
End If
End Sub

Code
Label1.FontItalic = True
End If
End Sub

Code
Label1.FontUnderline = True
End If
End Sub

Code
Label1.FontSize = 10
End If
End Sub

Code
End If
End Sub

Visual Basic Fundamentals
• Numeric constants: integer, long integers, single -
precision real (or floating point), double-precision real (or
floating point)
• String constants
• Variables
– Name must begin with a letter, letters and numbers
can be included, as well as underline character ( _ )
– Data-typing characters ( %, &, !, #, $) are not
permitted
– Maximum length of name = 255characters

Data types and data declaration
• Data types supported: Integer, Long,
Single, Double, String, Boolean, Byte,
Currency, Date
• Data declaration uses the Dim statement
Dim variable_name_1 As data_type_1,
variable_name_2 As data_type_2, etc.
Example:
Dim firstname as string

Branching and Looping
• Relational operators and logical expressions
– Relational operators: = , < > , < , <= , > , >=
– Logical expressions, e.g., a > b, c = d + 2, x >= y,
can be either true or false

If ..Then..Else..Endif Statement
If logical_expression Then
. . . . .
executable statements
. . . . .
Else
. . . . .
. . . . .
End If

Select Case Statement
Select Case expression
Case value1
Case value2
. . . . . . .
Case Else
End Select

For - Next Looping
For index = value1 To value2
. . . . . . .
. . . . . . .
Next index

Do - While Looping
Do While logical expression
. . . . . . . . . .
. . . . . . . . . .
Loop

VB Control Fundamentals
• Visual Basic control tools
* Check box
* Combo box
* Command Button
* Data
* Directory List Box
* Drive List Box
* File List Box
* Frame
* Horizontal Scroll Bar

• Visual Basic control tools
* Image Box
* Label
* Line
* List Box
* OLE Container
* Option Button
* Picture Box
* Pointer
* Shape
* Text Box
* Timer
* Vertical Scroll Bar

• Control tool categories
Entering Text Drawing
Text Box Line Button
Combo Box Shape Button

Displaying Text Selecting Among Alternatives
Label Check Box
Text Box Option Button
List Box Frame
Combo Box List Box

Displaying Graphics Viewing Windows
Image Box Frame
Picture Box Horizontal Scroll Bar
Frame Vertical Scroll Bar

Managing Files Accessing Existing Data
File List Box Data
Drive List Box
Directory List Box

Initiating Events Linking with Other Objects
Command Button OLE
Executing Timed Events
Timer

MsgBox
• Message boxes are used when you want to ask the
user a question or display an error message(s) and
advise the user
• There are six types of message boxes -
– vbOKonly
– vbOKCancel
– vbAbortRetryIgnore
– vbYesNoCancel
– vbYesNo
– vbRetryCancel

MsgBox
• Syntax
Msgbox “TEXT”, VALUE, “TITLE”
• Example 1
Msgbox “Sorry !!”, vbcritical, “Error”
• Example 2
Msgbox “Correct Password”, vbinformation, “Check”

Message box Example 1
• Design the following form
Label
Text Box Command Button

Code
• Double click on OK
MsgBox “Hello!!” + Text1
End Sub

Program Output

• Add a new form – FORM 2
• Click on Project in the Menu bar
• Click on Add Form

Program Output

Solution
• Double Click on OK
MsgBox Text1 + “ Loves ” + Text2
End Sub

Program Output

Code
• Double click on OK
MsgBox Text1 + “ ” + Text3 + “ ” + Text2
End Sub

If..Then..Elseif..Else..Endif Statement
If logical_expression Then
. . . . .
. . . . .
ElseIf logical_expression Then
. . . . .
. . . . .
various ElseIf clauses
. . . . .
Else
. . . . .
. . . . .
End If

Example1 - List Box
List Box

Code
• Double click on form1
Private Sub Form_Load()
List1.AddItem “……”
List1.AddItem “Red”
List1.AddItem “Yellow”
List1.AddItem “Green”
List1.AddItem “Blue”
End Sub

Code
• Double click on List1
Private Sub List1_Click()
If List1 = “Red” Then
ElseIf List1 = “Yellow” Then
ElseIf List1 = “Green” Then
Form1.BackColor = vbGreen
ElseIf List1 = “Blue” Then
Else
End If
End Sub

Example 2: Grade Calculation
• Design the form2

Code
• Double click on Command Button Total
Text5 = Val(Text3) + Val(Text4)
End Sub

Code• Double click on Command Button Grade
If Val(Text5) >= 80 And Val(Text5) <= 100 Then
Text6 = “A”
ElseIf Val(Text5) >= 60 And Val(Text5) <= 79 Then
Text6 = “B”
Text6 = “C”
ElseIf Val(Text5) >= 0 And Val(Text5) <= 39Then
Text6 = “F”
Else
Text6 = “ ”
MsgBox “Error!!”
End If
End Sub

Code
• Double click on Command Button Clear
Text1 = Clear
Text2 = Clear
Text3 = Clear
Text4 = Clear
Text5 = Clear
Text6 = Clear
End Sub

Code
• Double click on Command Button Exit
End
End Sub

Form1 - frmmain

Double click on confirm
If Option1 = True Then
frmoneway.Show
frmmain.Hide
ElseIf Option2 = True Then
frmroundtrip.Show
frmmain.Hide
Else
MsgBox "Please select a trip"
End If
End Sub

Double click on cancel
MsgBox “Thankyou!!”
End
End Sub

Form2 - frmoneway

Double click on frmoneway
Label2 = Date
Label3 = Time
Combo1.AddItem “F101”
End Sub

Double click on Combo1_Click
Private Sub Combo1_Click()
If Combo1 = “F101” Then
Text1 = “Bangkok”
Text2 = “Chiangmai”
Text3 = 1000
Text4 = 200
ElseIf Combo1 = “F102” Then
Text1 = “Chiangmai”
Text3 = 1000
Text4 = 200

Double click on Combo1_Click
ElseIf Combo1 = “F103” Then
Text2 = “Phuket”
Text3 = 1500
Text4 = 200
Else
MsgBox "Please select your flight no"
End If
End Sub

Double click on confirm
MsgBox “Thankyou!! Enjoy your trip”
End
End Sub

Double click on cancel
unload me
frmmain.show
End Sub

Form 3: frmroundtrip

If..Then..Elseif..Else..Endif
Exercise

Grade Criteria
Total Grade
90-100 A+
80-89 A
70-79 B+
60-69 B
50-59 C+
40-49 C
0-39 F
>100 or < 0 Error!!

Solution
• Double click on Command1 Grade
If Val(Text2) >= 90 And Val(Text2) <= 100 Then
Text3 = “A+”
Text3 = “A”
ElseIf Val(Text2) >= 70 And Val(Text2) <=79 Then
Text3 = “B+”
Text3 = “B”
Text3 = “C+”
Text3 = “C”
Text3 = “F”
Else
Text3 = “Error!!”
End If
End Sub

Example Timer
Label
Timer

Property of Timer1
• In the property of Timer1
Interval 600

Code for Timer1
• Double click on Timer1
Private Sub Timer1_Timer()
If Label1.Visible = True Then
Label1.Visible = False
Else
Label1.Visible = True
End If
End Sub

Example 2
• Determine the greater number

On Run mode

Click GO

Solution
• Double click on Command1 GO
If Val(Text1) > Val(Text2) Then
MsgBox “B is smaller, B= ” + Text2
Else
MsgBox “A is smaller, A= ” + Text1
End If

Password validation
Label
Text Box
Command
Button

Code
• Double click on Command Button1 Login
Dim password As String
password = “lcct”
If Text1 = password Then
password = MsgBox(“You have passsed security!!”, vbOKOnly +
vbExclamation, “Access Granted”)
Else
password = MsgBox (“Incorrect Password!!”, vbRetryCancel +
vbCritical, “Access Denied”)
If password = vbRetry Then
Text1 = ""
Text1.SetFocus
End If
End If
End Sub

Select Case
• The Select Case structure tests whether the value
of an expression falls within predetermined ranges.
• Syntax
Select Case expression
Case testlist
{instructions}
Case testlist
{instructions}
:
Case else
{instructions}
End Select

Example: Program to enter your age
Text Box

• Double click on
Dim age as Integer
age=text1
Select case age
case 1 to 12
Msgbox (“Child”)
case 13 to 19
Msgbox (“Teenager”)
case is > 19
Msgbox (“Adult”)
case else
Msgbox (“Impossible”)
End select
OK

Example: Program to insert any string

Program Explanation
• Use Select Case to do the program
• When the user enters blank string
– Display Message box “Null / Blank String”
• When the user enters a or e or I or o or u
– Display Message box “Vowel”
• When the user enters a to z
– Display Message box “Consonant”
• When the user enters 0 to 9
– Display Message box “Numeric Digit”
• When the user enters any other characters
such as $ or @ or *
– Display Message box “Special Character”

• Double click on
Dim str As String
str = Text1
Select Case Left(str, 1)
Case “”
MsgBox (“Null String”)
Case “A”, “E”, “I”, “O”, “U”, “a”, “e”, “i”, “o”, “u”
MsgBox (“Vowel”)
Case “A” To “Z”, “a” To “z”
MsgBox “Consonant”
Case “0” To “9”
MsgBox “Numeric Digit”
Case Else
MsgBox “Special Character”
End Select
OK

Hotel Example

Select Case Combo1
Case “Single”
Text1 = (Val(Text2) * 500) & “ Baht ”
Case “Single A/C”
Case “Double”
Case “Double A/C”
Case “HoneyMoon Suite”
End Select
End Sub

Select case - Example

Code
• Double click on Form
Combo1.AddItem "English"
Combo1.AddItem "Thai"
Combo1.AddItem "Japanese"
Combo1.AddItem "Chinese"
Combo1.AddItem "India"
End Sub

Code
• Double click on Combo1
Private Sub Combo1_Click()
Select Case Combo1
Case "English"
Text1 = "Hello"
Case "Thai"
Text1 = "Suwadee"
Case "Japanese"
Text1 = "Konichiwa"
Case "Chinese"
Text1 = "Nihaw"
Case "India"
Text1 = "Namaste"
End Select
End Sub

Option Button & Frames - Example
Frame
Option Button
Label

Code
Label1.FontBold = True
End Sub
Label1.FontBold = False
End Sub
Label1.FontItalic = True
End Sub
Label1.FontItalic = False
End Sub
Label1.FontUnderline = True
End Sub
Label1.FontUnderline = False
End Sub

Code
End Sub
End Sub
End Sub

Code
Label1.ForeColor = vbBlue
End Sub
Label1.ForeColor = vbRed
End Sub
Label1.ForeColor = vbYellow
End Sub
Label1.ForeColor = vbGreen
End Sub

Quiz Example

Code
• Double click on Score, Command Button1
Dim answer As Integer
If Option2.Value = True Then
answer = answer + 1
End If
answer = answer + 1
End If
answer = answer + 1
End If
If answer = 3Then
MsgBox “You scored 3”
ElseIf answer = 2 Then
End If
End Sub

For Loop Example
Combo Box

Code
• Double click on Command Button 1 Add Number
Combo1.AddItem Text1
Text1 = ""
Text1.SetFocus
End Sub
• Double click on Command Button 2 Count
MsgBox “Total items = ” & Combo1.ListCount
End Sub

Code
• Double click on Command Button 3 Maximum
Dim Max As Integer
Dim i As Integer
Max = 0
For i = 0 To Combo1.ListCount - 1
If Combo1.List(i) > Max Then
Max = Combo1.List(i)
End If
Next i
MsgBox “Maximum Number = ” & Max
End Sub

Code
• Double click on Command Button 4 Minimum
Dim Min As Integer
Dim i As Integer
Min = 100
If Combo1.List(i) < Min Then
Min = Combo1.List(i)
End If
Next i
MsgBox “Minimum Number = ” & Min
End Sub

Code
• Double click on Command Button 5 Sum
Dim sum, i As Integer
sum = sum + Val(Combo1.List(i))
Next i
MsgBox “Sum=” & sum
End Sub

Code
• Double click on Command Button 6 Average
Dim average, sum, i As Integer
sum = sum + Val(Combo1.List(i))
Next i
average = Val(sum) / Combo1.ListCount
MsgBox “Average = ” & average
End Sub

Designing a Menu Bar
• What is a Menu Bar ?
– A menu bar is used to display a list of items from where
an user can select any one item.

Example: Menu Bar
• Click on the Menu Editor in the Tool Bar
• In the caption, type File
• In the name, type mnufile
• Click OK
• Run

Menu Editor
Menu Caption
Menu Name
Menu Shortcut Key
To add new menu
To insert new menu
Directions
(Left, Right, Up, Down)
To delete menu

Designing a Sub_Menu
• Click on Menu Editor in Toolbar.
• In Caption, type File
• In Name, type mnuFile
• Click on Next
• Click on Right Arrow Button
• In Caption, type Open
• In Name, type mnuOpen
• In ShortCut Key, Ctrl+O
• Click on Next
• In Caption, type -
• In Name, type mnublank1
• Click on Next
• In Caption, type New
• In Name, type mnuNew
• In ShortCut Key, Ctrl+N

Designing a Multiple menu
• In Caption, type File
• In Name, type mnuFile
• Click on Next
• In Caption, type Open
• In Name, type mnuOpen
• In ShortCut Key, Ctrl+O
• Click on Next
• Click on Next
• In Caption, type New
• In Name, type mnuNew
• In ShortCut Key, Ctrl+N

Designing the EDIT Menu
• Click on Left Arrow Button
• In Caption, type Edit
• In Name, type mnuEdit
• Click on Next
• In Caption, type Copy
• In Name, type mnuCopy
• In ShortCut Key, Ctrl+C
• Click on Next
• Click on Next
• In Caption, type Cut
• In Name, type mnuCut
• In ShortCut Key,
Ctrl+X
• Click on Next
• Click on Next
• In Caption, type Paste
• In Name, type mnuPaste
• In ShortCut Key,
Ctrl+V

Using the Data Control to
Interact with Databases
• The VB Data Control is used to attach an
existing database, providing a link
between your application and your data.
• Various controls - such as
– labels
– images
– text boxes
can be connected to the data control.

Creating a Database Application
Step 1
• Create a table in MS-Access
• Save as, student
• Enter any five records
Field Name DataType FieldSize
Code Number Integer
Name Text 50
Primary
Key

Step 2
• Design the following form in VB
Text Box
Data

Step 3
Connecting the Data Control
• Select Data1
• In the property window,
• Select Database Name - Student
• Select Record Source (Table Name) - Student
• Select Text1
• Select Data Source – Data1
• Select Data Field - Code
• Select Text2
• Select Data Source – Data1
• Select Data Field - Name

Create a table in MS-Access
Save Database as : grade
Save Table as: grade
Field name Fieldtype
S_Code Number
Name Text
G_Vb Text
G_Datastructure Text
G_P_A Text

Design the form grade in VB

• Double click on calculate G.P.A.
Text5 = (Val(Text3) + Val(Text4)) / 2
• Double click on addnew
Data1.Recordset.AddNew
Text1.SetFocus
Text1 = ""
Text2 = ""
Text3 = ""
Text4 = ""
Text5 = ""

• Double click on delete
Data1.Recordset.Delete
Data1.Recordset.Movefirst
Double click on edit
Data1.Recordset.Edit
Text1.SetFocus

• Double click on save
Data1.Recordset.Fields(“S_Code”) = Text1
Data1.Recordset.Fields(“Name”) = Text2
Data1.Recordset.Fields(“Grade_Vb”) = Text3
Data1.Recordset.Fields(“Grade_Datastructure”) = Text4
Data1.Recordset.Fields(“G_P_A”) = Text5
Data1.Recordset.Update
Data1.Recordset.refresh

Phone book Application

Designing Status bar
• Right click on the Toolbox
• Select Microsoft Windows Common Controls 6.0
• Click Ok
• Double click on the status bar
• Select the status bar
• Right click
• Click on Properties
• Select Panels

• Index 1
• Text Date
• Click on Insert Panel
• Index 2
• Text Time
• Click OK

Writing Code
• Double click on form
StatusBar1.Panels(1) = Date
StatusBar1.Panels(2) = Time
End Sub

Quiz Project
• Start MS-ACCESS 97
• Save Project as, Quiz
• Save Table 1 as, Computer_Quiz
• Save Table 2 as, Score_Quiz

Table 1 - Computer_Quiz
FieldName DataType
No Autonumber
Question Memo
Option1 Text
Option2 Text
Option3 Text
Answer Number

Table 2 - Score_Quiz
FieldName DataType
Code Autonumber
Name Text
Score Number

Start Visual Basic (VB)
Form1: Password

Code
• Double click on Command1 (SignIn)
If Text1 = “lcct” And Text2 = “lcct” Then
Unload Me
Form2.Show
Else
a = MsgBox(“Please Try Again”, vbCritical, vbOK)
Text1 = ""
Text2 = ""
Text1.SetFocus
End If
End Sub

Start Visual Basic (VB)
Form2: Quiz

Connect Data1 (On-line Computer Test)
• Select Data1
• In the property of Data1,
• Database name Quiz
• Recordsource Computer_Quiz

Code
• Double Click on Command 1
If Data1.Recordset(“Answer”) = Val(Text1) Then
MsgBox “Congratulations!! Correct”
Label9 = Label9 + 1
Data1.Recordset.MoveNext
Else
MsgBox “Sorry!! Wrong”
Data1.Recordset.MoveNext
End If
Text1 = ""
Text1.SetFocus

If Data1.Recordset.EOF Then
Data1.Recordset.MoveLast
Data2.Recordset.AddNew
Data2.Recordset(“Name”) = Text2
Data2.Recordset(“Score”) = Label9
Data2.Recordset.Update
Data2.Refresh
MsgBox “Thankyou for the test”
End
End If
EndSub

Designing Toolbar
Black Blue Red White Yellow

Select Case Button.Index
Case 1
Form1.BackColor = vbBlack
Case 2
Case 3
Case 4
Case 5
End Select

Select Case Button.Index
Case 1
notepad = Shell(“notepad”, vbNormalFocus)
Case 2
Form2.Show
Case 3
End
End Select

Visual Basic 6.0

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