Introduction to VB

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Chapter 1: An Introduction to
Visual Basic .NET
Programming with Microsoft Visual Basic
.NET, Second Edition
Creating a Windows-Based
Application in Visual Basic .NET
Lesson A Objectives
•
•
•
•
•
Start and customize Visual Studio.NET
Create a Visual Studio .NET solution
Add a Visual Basic .NET project to a solution
Set the properties of an object
Restore a property to its default setting
Programming with Microsoft Visual Basic .NET, Second Edition
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Creating a Windows-Based
Application in Visual Basic .NET
Lesson A Objectives (continued)
• Save a solution, project, and form
• Close a solution
• Open an existing solution
Programming with Microsoft Visual Basic .NET, Second Edition
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Starting and Customizing
Visual Studio .NET
• Visual Studio .NET is Microsoft’s newest
integrated development environment (IDE)
– Includes programming languages such as Visual
Basic .NET, C++ .NET, and C# .NET
• A Windows-based application has a Windows
user interface and runs on a desktop computer
• A user interface is what you see and interact with
when using an application
• A Web-based application has a Web user
interface and runs on a server
Programming with Microsoft Visual Basic .NET, Second Edition
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Starting and Customizing
Visual Studio .NET (continued)
• Windows in the Visual Studio .NET IDE:
–
–
–
–
–
–
Start Page
Solution Explorer
Server Explorer
Toolbox
Class View
Dynamic Help
Programming with Microsoft Visual Basic .NET, Second Edition
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Starting and Customizing
Visual Studio .NET (continued)
Figure 1-3: Projects pane in the Start Page window
Programming with Microsoft Visual Basic .NET, Second Edition
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Creating the Copyright Screen
Application
• Applications created in Visual Studio .NET are
composed of solutions, projects, and files
• A solution is a container that stores the projects
and files for an entire application
• A project is a container that stores files
associated with only a specific piece of the
solution
• To create an application:
– Create a blank Visual Studio .NET solution
– Add one or more projects to the solution
Programming with Microsoft Visual Basic .NET, Second Edition
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Creating the Copyright Screen
Application (continued)
Figure 1-6: New Project dialog box used to create a blank
solution
Programming with Microsoft Visual Basic .NET, Second Edition
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Creating the Copyright Screen
Application (continued)
Figure 1-9: New Visual Basic .NET project added to the solution
Programming with Microsoft Visual Basic .NET, Second Edition
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The Windows Form Designer
Window
• Windows Form Designer window is where you
create (or design) the graphical user interface
(GUI) for your project
• You create the user interface by adding other
objects (such as buttons and text boxes) to a
Windows Form object (or form)
Programming with Microsoft Visual Basic .NET, Second Edition
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The Windows Form Designer
Window (continued)
Figure 1-11: Windows Form Designer window
Programming with Microsoft Visual Basic .NET, Second Edition
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The Solution Explorer Window
• The Solution Explorer window displays:
– A list of projects contained in the current solution
– Items contained in each project
• The Solution Explorer window shows that the
Copyright Solution contains one project named
Copyright Project
• Within the Copyright Project is:
– A References folder
– Two files: AssemblyInfo.vb and Form1.vb
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The Solution Explorer Window
(continued)
Figure 1-12: Solution Explorer window
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The Properties Window
• Each object has a set of attributes, called
properties, that determine its appearance and
behavior
• The Properties window exposes the object’s
properties to the programmer
• The Properties window includes an Object box
and a Properties list
• The Properties window can be used to change a
property of an object
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The Properties Window (continued)
Figure 1-15: Properties window showing the properties of the
Form1.vb file object
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Properties of the Windows
Form Object
• The Windows Form object has a set of properties
• Properties of the Windows Form object will
appear in the Properties window when you select
the Windows Form object in the designer window
Programming with Microsoft Visual Basic .NET, Second Edition
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Properties of the Windows
Form Object (continued)
• Important properties of the Windows Form object:
–
–
–
–
–
Name property
Text property
StartPosition property
Size property
BackgroundImage property
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Saving a Solution
• Options for saving a solution:
– Click File on the menu bar, and then click Save All
– Click the Save All button on the Standard toolbar
– Select the solution’s name in the Solution Explorer
window, and then click the Save button on the
Standard toolbar
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Closing the Current Solution
• You close a solution using the Close Solution
option on the File menu
• When you close a solution, all projects and files
contained in the solution also are closed
• If unsaved changes were made to the solution,
project, or form, a dialog box opens and prompts
you to save the appropriate files
Programming with Microsoft Visual Basic .NET, Second Edition
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Opening an Existing Solution
• To open an existing solution:
– Click File on the menu bar and then click Open
Solution
– Select the appropriate solution file in the Open
Solution dialog box
• Only one solution can be open in the IDE at any
one time
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Exiting Visual Studio .NET
• You exit an application using either:
– The Close button on the application window’s title
bar
– The Exit option on the File menu
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Working with Controls
Lesson B Objectives
• Add a control to a form
• Set the properties of a label, picture box, and
button control
• Select multiple controls
• Center controls on the form
• Set the properties of a project
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Working with Controls
Lesson B Objectives (continued)
• Start and end an application
• Enter code in the Code Editor window
• Terminate an application using the Me.Close
method
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The Toolbox Window
• The Toolbox window, or toolbox, contains the
tools and other components you use when
designing a user interface
• The contents of the toolbox vary depending on
the designer in use
• Tools in the toolbox allow you to create objects,
called controls, that can be displayed on a form
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The Toolbox Window (continued)
• The Windows Form tab
– Contains the tools you use when designing your
user interface
– Contains 47 basic tools
– You can add new tools or delete existing tools
• By default, the tools on the Windows Form tab
are listed in order by their estimated frequency of
use, with the most used tools listed first
Programming with Microsoft Visual Basic .NET, Second Edition
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Using the Label Tool
• You use the Label tool to create a label control
• The purpose of a label control is to display text
that the user is not allowed to edit while the
application is running
• Assigning meaningful names to the controls on a
form will help you keep track of the various
controls in the user interface
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Using the Label Tool (continued)
• Used to display data that users cannot change
Property
Description
Name
Identifies the object in code
Text
Displays information
AutoSize
Determines if the object resizes
itself to display all Text
Location
Sets the X and Y coordinates for
where label is displayed
Font
Characteristics of the displayed
Text
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Changing the Property for
More Than One Control at a Time
• You can use the Font property to change the
appearance of many of the objects in your user
interface
• The Font property allows you to change the type,
style, and size of the font used to display the text
in the object
• A font is the general shape of the characters in
the text
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Changing the Property for
More Than One Control at a Time
(continued)
• Font sizes are typically measured in points, with
one point equaling 1/72 of an inch
• One reason for changing a font is to bring
attention to a specific part of the screen
• You can change the font size for both controls at
the same time by clicking one control and then
pressing and holding down the Control key as
you click the other control in the form
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Changing the Property for
More Than One Control at a Time
(continued)
• You can use the Control+Click method to select
as many controls as you want
• To cancel the selection of one of the selected
controls, press and hold down the Control key as
you click the control
• To cancel the selection of all of the selected
controls, release the Control key, then click the
form or an unselected control on the form
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Using the Format Menu
• Align option aligns two or more controls by their
left, right, top, or bottom borders
• Make Same Size option makes two or more
controls the same width and/or height
• Center in Form option centers one or more
controls either horizontally or vertically on the
form
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Using the PictureBox Tool
• You can include a logo by displaying the logo in a
picture box control, which you create using the
PictureBox tool
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Using the Button Tool
• Every Windows application should give the user
a way to exit the program
– Most Windows applications provide either an Exit
option on a File menu or an Exit button for this
purpose
• In Windows applications, a button control
performs an immediate action when clicked
• You create a button using the Button tool in the
toolbox
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Starting and Ending an Application
• You can start an application by:
– Clicking Debug on the menu bar, and then clicking
Start
– Or, pressing the F5 key on your keyboard
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Starting and Ending an Application
(continued)
• You can stop the copyright screen application by:
– Clicking the Close button on the form’s title bar
– Or, clicking the designer window to make it the
active window, then clicking Debug on the menu
bar, and then clicking Stop Debugging
– Or, pressing Shift+F5
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Writing Visual Basic .NET Code
• Users actions—such as clicking, double-clicking,
and scrolling—are called events
• The set of Visual Basic .NET code that tells an
object how to respond to an event is called an
event procedure
• A class definition is a block of code that specifies
(or defines) the attributes and behaviors of an
object
Programming with Microsoft Visual Basic .NET, Second Edition
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Writing Visual Basic .NET Code
(continued)
• The Class Name list box lists the names of the
objects included in the user interface
• The Method Name list box lists the events to
which the selected object is capable of
responding
• Code Editor provides you with a code template
for every event procedure
• First line in the Code template is the procedure
header
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Writing Visual Basic .NET Code
(continued)
• Last line in the Code template is the procedure
footer
• A keyword is a word that has a special meaning
in a programming language
• The Sub keyword refers to a block of code that
performs a specific task
• The Private keyword indicates that the procedure
can be used only within the class in which it is
defined
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Writing Visual Basic .NET Code
(continued)
• Parameters represent information that is passed
to the procedure when it is invoked
• A method is a predefined Visual Basic .NET
procedure that you can call (or invoke) when
needed
• When you call the Me.Close method, Visual
Basic .NET terminates the current application
Programming with Microsoft Visual Basic .NET, Second Edition
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Writing Visual Basic .NET Code
(continued)
Private Sub uiExitButton_Click(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles uiExitButton.Click
Private Sub
Indicates the start of a code unit that can
only be used in this class
uiExitButton_Click
The name of the procedures is the object
name and event name connected with an
underscore
sender As Object
Identifies the object creating the event
e As
System.EventArgs
Identifies specific information about the
event
Handles
Identifies the object and event that this
procedure will handle
The uiExitButton’s Click event procedure
Programming with Microsoft Visual Basic .NET, Second Edition
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Writing Visual Basic .NET Code
(continued)
Private Sub uiExitButton_Click(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles uiExitButton.Click
Me.Close()
End Sub
The event procedure
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Completing the Copyright Screen
Lesson C Objectives
•
•
•
•
•
Set the properties of a timer control
Delete a control from the form
Delete code from the Code Editor window
Code the timer control’s Tick event
Remove and/or disable the Minimize, Maximize,
and Close buttons
• Prevent the user from sizing a form
• Print the project’s code
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Using the Timer Tool
• Splash screens typically use a timer control to
automatically remove the splash screen after a
set period of time
• You create a timer control using the Timer tool in
the toolbox
• You can use a timer control to process code at
regular time intervals
• You set the timer control’s Interval property to the
length of the desired time interval, in milliseconds
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Using the Timer Tool (continued)
• You also set its Enabled property to True
• The Enabled property determines whether an
object can respond to an event
• You then enter the code you want processed into
the control’s Tick event procedure
• The Tick event procedure tells the computer what
to do after each time interval has elapsed
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Using the Timer Tool (continued)
Figure 1-35: Timer control placed in the component tray
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Setting the FormBorderStyle
Property
• The FormBorderStyle property determines the
border style of a Windows Form object
FromBorderStyle
setting
Description
Fixed3D
Fixed, three-dimensional
FixedDialog
Fixed, thick dialog-style
FixedSingle
Fixed, thin line
FixedToolWindow
Fixed, tool window style
None
No border
Sizable
Sizable, normal style (default)
SizableToolWindow
Sizable, tool window style
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The MinimizeBox, MaximizeBox,
and ControlBox Properties
• You can use a Windows Form object’s
MinimizeBox property to disable the Minimize
button
• You can use the MaximizeBox property to disable
the Maximize button
• Splash screens typically do not contain a title bar
• You can remove the title bar by setting the
Windows Forms object’s ControlBox property to
False, and then removing the text from its Text
property
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Printing Your Code
• You always should print a copy of the code
entered in the Code Editor window, because the
printout will help you understand and maintain
the application in the future
• To print the code, the Code editor window must
be the active, or current, window
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Summary
• To create a blank solution, click File on the menu
bar, point to New, and then click Blank Solution
• You can add a new project to the current solution
by clicking File on the menu bar, pointing to Add
Project, and then clicking New Project
• To save a solution, click File on the menu bar,
and then click Save All
• To open an existing solution, click File on the
menu bar, and then click Open Solution
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Summary (continued)
• To add a control to a form, click the appropriate
tool in the toolbox, but do not release the mouse
button, drag the mouse pointer to the form, and
release the mouse button
• To select multiple controls, click one control, then
Control+click each of the other controls
• One way to open the Code Editor window is to
right-click anywhere on the form (except the
form’s title bar), and then click View Code on the
context menu
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Summary (continued)
• Use the Timer tool to perform code at specified
intervals of time
• Set the form’s FormBorderStyle property to
control the border style of the form
• To print the Visual Basic .NET code, open the
Code Editor window, click File on the menu bar,
click Print, and then click the OK button in the
Print dialog box
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