Chapter 1

Getting Started with VB .NET

Objectives

• Learn about VB .NET and the characteristics of a VB .NET solution

• Start and configure VB .NET• Explore the elements of the development

environment• Learn how to access Help• Open a VB .NET solution• Explore the tool windows and operating

modes of VB .NET

Introducing Visual Studio .NET (1)

• Visual Studio .NET is an integrated development environment

• Development environment supports three different languages– Visual Basic– Visual C++– C# (pronounced C sharp)

• New to Visual Studio .NET

– Note that Visual Interdev is obsolete. Functionality included with other Visual Studio .NET products

Introducing Visual Studio.NET (2)

• Applications (called solutions) developed using a developer interface called the Microsoft Development Environment (MDE)

• VB .NET supports different types of applications created with the following tools– Windows Forms used to create desktop applications– Web Forms used to create programmable Web

pages– Web Services process client – server requests

Differences Between VB 6 and Visual Studio .NET

• VB 4, 5, and 6 were backward compatible– VB .NET is not backward compatible– VB 6 programs require significant modification to run

under VB .NET

• VB .NET incorporates new object oriented programming features

• VB .NET adheres to the Common Language Specification (CLS) for language interoperability

• ADO.NET replaces ADO– ADO.NET operates better with Web applications

Facts About Programming Languages (1)

• Programming language made up of words forming statements

• A Statement expresses a complete thought or idea– Similar to an English sentence

• Statements grouped into procedures– A procedure is similar to a paragraph in English

• Procedures grouped into a module– Modules contain one or more procedures

– Modules correspond to physical disk files

– Module files have the suffix .vb.

Facts About Programming Languages (2)

• A program contains statements, grouped into procedures, in one or more modules– VB .NET calls a program a solution

• Each solution is stored in its own folder– Solution folder contains sub folder– Solution folder contains all of the files that

make up the solution

Program Relationships

Public Class frmMain

Inherits System.Windows.Forms.Form

Private components = New System.ComponentModel.Container

End Class

Public Class frmDialog . . .End Class

Public Sub New()

End Sub

Public Sub InitializeComponent()

End Sub

MyBase.New()InitializeComponent()

Me.Text = "Chapter 1 – Completed Example

Procedure

Procedure

Module filefrmMain.vb

Module filefrmDialog.vb

Executablestatements

Executablestatement

Types of Statements

• Declaration statements define the names of data and procedures

• The following statements declare a variable and a procedure

Private mstrCustomerName As String

Private Sub InitializeComponent()End Sub

• Executable statements perform a specific action• The following statement closes the form named frmMain

frmMain.Close()

Syntax

• Programming statements adhere to rules known as syntax– Statements must be exactly correct– VB .NET cannot interpret statements with

typographical or spelling errors– Incorrect statements will cause a syntax error

• Syntax errors occur when a statement violates the rules of the language

Private mstrCustomerName As StrungfrmMain.Closed()

Private mstrCustomerName As StrungfrmMain.Closed()

VB .NET Programming Concepts

• VB .NET solutions have the same characteristics as other programs

• Window is a rectangular area on the desktop– Win Form (form) contains buttons and boxes

• Buttons, boxes, and the form itself are all windows

– Solutions contain 1 or more forms– Collection of forms, buttons, and boxes form the user

interface• User interface represents what the user sees and how

the user interacts with the solution

Object Oriented Terms (1)

• Information hiding – Expose only essential information and hide inner logic

• Encapsulation – Integrate (package) data and processes that act on data together– Inner logic is hidden from the developer

• Inheritance – Create new objects from existing objects– Inherit one form from another form

• Polymorphism – Multiple procedures of the same name perform different tasks– Capable of taking many forms

Object Oriented Terms (2)

• Programming object mimics the behavior of a real-world object– Buttons on a form perform a task when clicked

• Some objects are visible to the user – others are not• Objects are created from classes

– Multiple objects can be created from the same class. For example, create multiple buttons on a form

• A class is a blueprint (template) for an object– Buttons on a form created from the Button class

– Boxes created from the TextBox class

The Technical View of a VB .NET Solution (1)

• An object has:– Predefined behaviors or settings called properties

• Properties exist to define the size and position of a button on a form, for example

– Methods represent the actions an object can perform– Events allow messages to be sent to a solution

• Write code in event handlers also known as event procedures

• When the user clicks a button, statement in the corresponding event handler execute

The Technical View of a VB .NET Solution (2)

• Use controls to create objects appearing on a form• A control created on a form is called a control

instance– Button control is a button the user can click– Label control displays text but cannot receive input– OpenFileDialog control displays a standard dialog box

allowing user to select a file– PictureBox control displays pictures

• All control instances created from their respective class

Sample of VB .NET Controls

Label control instance to display a descriptive prompt

Label control instance to display file name

PictureBox control instance to display graphical image

Buttons when clicked perform an action

OpenFileDialog control instance has no visual interface and appears in a tray at the bottom of the form

Starting VB .NET

Start button

Microsoft Visual Studio.NET 7.0

Configuring VB .NET (1)

• VB .NET supports two operating modes– Tabbed documents environment

• Docked windows appear along edge of the MDE

• Docked windows can be temporarily hidden

• Floating windows appear anywhere on the desktop

• Windows can be autohidden along any edge of the MDE

– Multiple document interface• Appearance similar to Excel

• Not used in this book

Configuring VB .NET (2)

• On the Menu bar, click Tools, and then click Options to display Options dialog box– General tab sets environment (tabbed

documents or MDI mode)– Projects and Solutions tab sets default folder

for projects and when changes are saved

VB .NET Options Dialog Box – General Tab

Select folder

Active page highlighted

VB .NET Options Dialog Box – Projects and Solutions Tab

Default project location

VB .NET Window Types

Docked window

Document window

Autohidden window

Floating window

Configuring the Menu Bar and Toolbar

• Multiple regions display toolbars– Regions appear along any edge of the MDE– Individual toolbars can be hidden or made visible

depending on task at hand– Use Customize dialog to configure toolbars

• Floating toolbars appear anywhere on the desktop

• Docked toolbars anchored along any edge of the MDE– Usually they appear below the menu bar though

Docked and Floating Toolbars

Docked toolbar

Floating toolbar

Toolbars docked along bottom of MDE

Document Windows

• Appear on group tabs and correspond to the individual files that make up a solution– Win Form Designer used to create the user interface– Code Editor used to write statements in event

handlers– Only one document window visible at a time– Select window on group tab to activate desired

document window

• Buttons to the right of a group tab navigate between document windows and close them

Tool Windows

• The same tool windows are used in the creation of all VB .NET solutions– Solution Explorer groups all elements needed to

build and run a solution– Properties window allows developer to manage the

appearance of each object– Help windows are also tool windows

• Tool windows can be:– Docked – appearing along an edge of the MDE– Autohidden – hidden along an edge of the MDE– Floating – appearing anywhere on the desktop

Document Windows and Tool Windows

Document windows appear on tab group

Close active document window

Solution Explorer is a tool window (appearing as a docked window

Configuring Tool Windows (1)

• Make a window float by right-clicking on the title bar and select Floating

• Autohide a window by first docking the window. Right-click the title bar and select Autohide

• Dock a window by right-clicking the title bar and select dockable. Drag the window to an edge of the MDE

• Configure windows as desired so that they best fit your needs

Configuring Tool Windows (2)

Docked window

Autohidden windows appear along an edge of the MDE

Getting Help

• VB .NET supports four primary help windows– Index – alphabetical list of contents– Contents – table of contents organized by topic– Search – locate topics by keyword– Dynamic Help – new to .NET

• Display topics based on active window and current task

• Topics that appear in the Dynamic Help window will change as you navigate from window to window

• Help filters restrict information displayed

Help – Index

Filter applied

Index tab

Applicable topics

Help – Contents

Topic

Book expanded

Help – Search

Search results

Search text

Help – Dynamic Help

Dynamic Help Window

Opening a VB .NET Solution

• Click File, and then click Open Solution

Enter solution name

Select folder

Click to Open solution

Organization of a VB .NET Solution

• Solution file is at the heart of the application– Controls how solution will be translated into

executable file– Controls how application will be distributed– File suffix is .sln

• Solution file references one or more project files which:– Store global information– List the other files in the project– List references to namespaces

Form Modules

• Projects can contain multiple forms

• Each form stored in a form module– Form module contains code to create control

instances– Also contains code written by the developer to

perform tasks– File suffix is .vb

• Do not change file suffix or VB .NET will not be able to locate files

Elements of a Solution

solution filesolution file

form module frmMain.vbform module frmMain.vb

form module frmDialog.vbform module frmDialog.vb

class module clsDemo.vbclass module clsDemo.vb

standard module stdDemo.vbstandard module stdDemo.vb

Bin folder contains compiled solutionBin folder contains compiled solution

Obj folder contains temporary filesObj folder contains temporary files

solution itemssolution items

text filetext file

icon filesicon files

miscellaneous filesmiscellaneous files

project fileComplete01.vbproj

project fileComplete01.vbproj

The Solution Explorer

• Groups projects and modules comprising a solution

Properties Window (1)

• Property is a characteristic of an object– Color, caption, screen location

• Set properties using the Properties window– Name column lists property– Value column contains current value– Display properties alphabetically or by category– Description of selected appears at the bottom of

the window• Description section may be hidden

Properties Window (2)

Object list boxObject list box

Selected Font property has subproperties

Selected Font property has subproperties

Description areaDescription area

Toolbar areaToolbar area

Toolbox

Visual controls appear in the Toolbox

Visual controls appear in the Toolbox

Operating Modes

• Three operating modes– In run mode VB .NET is executing the

program• Program appears as the user will see it

– In design mode you assume the role of the developer

– In break mode solution is temporarily suspended

• Use for debugging• Refer to Appendix A for information on debugging

Running a Solution

• Press Start button on the Debug toolbar– Solution runs as the user will see it

• Press Stop Debugging button on the Debug toolbar to end the solution and return to design mode