CHAPTER TWO
Creating Simple Visual Basic
.NET Windows Applications
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Chapter Introduction
• The Integrated Development Environment (IDE)
is used for modern software development.
• The IDE contains tools to write code, build a
GUI , and test and debug applications.
• Overview of the application construction
process.
• Design issues are addressed.
• Visual Basic .NET controls are examined.
• The MsgBox statement and InputBox() function
are visited.
• A project is developed as a working application.
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Objectives
• Design and construct simple complete
applications from scratch.
• Explain the structure of Visual Basic .NET.
• List the characteristics of several Visual
Basic .NET controls.
• Identify the purpose of each major control
of the Visual Basic .NET IDE.
• Explain basic programming practices that
contribute to the readability of programs.
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2.1 From New Solution to Finished
Application
• Overview of the Construction Process
– Visual Basic .NET runs under Windows.
– The programmer creates the application.
– The project is an application under
construction.
– The application is saved to disk periodically.
– An executable file is generated from the
finished application program.
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Visual Basic .NET’s Three Modes
• Design Mode
– Placing, arranging, and customizing the
appearance of buttons, labels, and other
controls on a form.
– Writing processing scripts (source code).
– Saving the solution.
– Making an executable file.
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Visual Basic .NET’s Three Modes
(cont.)
• Run Mode
– Executes the solution.
– Used to evaluate the workability of a part of
the project.
– Used to show the user how the solution will
work.
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Visual Basic .NET’s Three Modes
(cont.)
• Break Mode
– Helps the developer with debugging.
– Enables the developer to switch back to run
mode or design mode.
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Design Time and Run Time
• In design mode, the project is in design
time.
• In run mode, the project is in run time.
• Some errors can be found and corrected
in design time.
• Other errors can only be detected during
run time.
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2.2 Overview of Controls
• Standard controls are used to create userfriendly applications.
• Standard controls help users lower the
learning curve for new programs.
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Categories of Controls
• Trigger: Initiate processing
– Ex. Button, MainMenu, and Timer
• Input: Get data from user
– Ex. TextBox, RadioButton, and CheckBox
• Output: Display results to user
– Ex. Label, DataGrid, and ListView
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Categories of Controls (cont.)
• Organize: Group other controls
– Ex. Form, GroupBox, and Panel
• Data Access: Interface with databases
– Ex. Entire Data Group and DataGrid
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The Correct Control for the Job
• Chose controls to satisfy user
requirements.
• Different controls are good for different
tasks.
• The Button, Label, and Textbox controls
are introduced.
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2.3 The Visual Basic .NET
Development Environment
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• The IDE helps develops create efficient
and effective solutions.
• The IDE for Visual Basic .NET is common
to all the other tools available in the Visual
Studio. NET suite.
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Getting Started
• Open an existing project or begin a new
project from the Start Page.
• Use the My Profile option to set up the
IDE.
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Visual Basic .NET Solution
Structure
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• Every application will be organized as a
“solution.”
• Solution Explorer is an interface for
viewing and managing containers and
associated items.
• Items are files that make up your project,
such as forms, source files, and classes.
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Main Tools Used in Visual Basic
.NET
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Menu
Toolbar
Solution Explorer
Properties Editor
Task List
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Toolbox
Designer Window
Code Window
Help System
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Saving a Solution
• Save your solution and all its contents on
a regular basis.
• Each project should be in its own separate
folder.
• Avoid the temptation to use the Save
As…, save option.
• Use the Save and Save All Toolbar icons.
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Summary
• Many of the features of the Visual Basic
.NET IDE have been introduced.
• Next, some of the controls to write simple
programs will be introduced.
• Experimentation is encouraged.
• Hands-on experience is important.
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2.4 Introducing the Windows Form
Control
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• The window that is displayed when the
application is running.
• The IDE automatically creates a Windows
Form when you start a new project.
• This form will hold or “contain” other
controls.
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2.5 The Button Control
• React to the click of the use
• Perform a task associated with the name
of the button that is displayed on its face.
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Appearance and Use
• Appears as a rectangular-shaped control
on a form.
• Its face can display text, an image, or
both.
• The face of the button should clearly
indicate its function.
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Properties
• The most common properties of the Button
control are listed.
• Most properties are available for every
control.
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Common Properties of the Button
Control
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Name
BackColor
BackgroundImage
Enabled
Font
ForeColor
Image
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ImageAlign
TabIndex
TabStop
Text
TextAlign
Visible
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Events
• Components are able to respond to
events.
• The click event is generated when the
user clicks the mouse button.
• You write code to handle events.
• Double-click the Button control to
automatically open the code window.
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2.6 The Label Control
• Used to display information to the user.
• Used to label other controls or show
results of a calculation.
– Ex. Check box and radio button labels.
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Appearance and Use
• Appears as a rectangular area that can be
filled with text.
• You have some control over size and
alignment of text.
• You can include a border around the label.
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Properties
• Many of the Button control properties
apply to the Label control.
• The Text Property is the most-used
property for the Label control.
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Common Properties of the Label
Control
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Name
AutoSize
BorderStyle
DataBindings
Font
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ForeColor
Image
ImageAlign
Text
TextAlign
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Events
• Example 2.1 Using the Label Control
– Demonstrates two main uses of the Label
control
• To display a message to the user.
• To display “labeling” information for the user.
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2.7 The TextBox Control
• Provides an area for the user to type while
the program runs.
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Appearance and Use
• Displays as a rectangular area that
provides the user a place to type.
• You can limit the user types
• You can also surround the TextBox with a
border.
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Properties
• Some of the TextBox control properties are
only available at run time.
• The value of the Text property is used
most frequently.
• Control of user entry is shared between
properties and events.
• The PasswordChar property allows you to
set a security character.
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Properties (cont.)
• TextLength property determines the
number of characters contained in a
textbox.
• Selection… properties provide information
on user selections in the TextBox control.
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Common Properties of the TextBox
Control
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Name
AcceptsReturn
AcceptsTab
AutoSize
BorderStyle
CharacterCasing
Font
Lines
MaxLength
Modified
Multiline
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PasswordChar
ReadOnly
ScrollBars
SelectedText
SelectionLength
SelectionStart
Text
TextAlign
TextLength
WordWrap
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Events
Focus means the user is currently working
with the specific control.
• Enter - Occurs when input focus is
received.
• KeyPress - Occurs when a key is pressed
while the control has focus.
• Leave – Occurs when input focus leaves
the control.
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Events (cont.)
• Methods
– Enable the developer to manipulate text in a
TextBox.
– Many are available to the developer.
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Common Events for the TextBox
Control
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Enter
KeyPress
Leave
AppendText
Clear
Copy
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Cut
Cut
Paste
Select
SelectAll
Undo
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2.8 The MsgBox Statement and
InputBox Function
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• Two alternate ways to receive information
from the user and to display information on
the screen.
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MsgBox Statement
• The MsgBox statement will display
information that requires user intervention.
– MsgBox(“A prompt”, Buttons,”A title”)
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InputBox() Function
• The InputBox() function requests
information from the user with a dialog
box. It requires user intervention.
– InputBox(“A prompt”,”A title”,”A default
response”)
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Chapter Summary
• An application being developed in Visual
Basic .NET is called a project.
• Visual Basic .NET uses three modes of
operation.
• The Visual Basic .NET IDE contains a
number of development tools.
• During the design phase, descriptive names
should be applied to important controls.
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Chapter Summary (cont.)
• The Windows Form control is used to contain
the other GUI controls.
• The Button control enables the user to trigger
a process by a click event.
• The MsgBox statement provides an alternate
means to provide information to the user.
• The InputBox() function provides an alternate
way to receive information from the user.
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