Lecture Learning programming using Visual Basic Net – Chapter 2 Creating simple Visual Basic NET windows applications

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
•
•
•
•
•

Menu
Toolbar
Solution Explorer
Properties Editor
Task List

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•
•
•
•

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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.
ã 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.
ã Most properties are available for every

control.

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Common Properties of the Button
Control
ã
ã
ã
ã
ã
ã
ã

Name
BackColor
BackgroundImage
Enabled
Font
ForeColor
Image
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ã
ã
ã
ã

ã
ã

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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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