Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf

8/14/2019 Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksj…

http://slidepdf.com/reader/full/aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf 1/36

1-1

aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf

aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf



aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf



Introduction to VisualBasic.NET 2005

Chapter 11

McGraw-Hill © 2006 The McGraw-Hill Companies, Inc. All rights rese



1-3

Chapter Objectives (1 of 2)

Describe the process of visual program design anddevelopmentExplain the term object-oriented programming

Explain the concepts of classes , objects , properties ,methods , and eventsList and describe the three steps for writing a Visual

Basic projectDescribe the various files that make up a Visual Basic

project



1-4

Chapter Objectives (2 of 2)

Identify the elements in the Visual StudioenvironmentDefine design time , run time , and debug timeWrite, run, save, print, and modify your first Visual

Basic projectIdentify syntax errors , run-time errors , and logic

errorsUse Auto Correct to correct syntax errorsLook up Visual Basic topic in Help



1-5

Writing Windows Applications with VB(1 of 2)

Windows Graphical User (GUI) InterfaceDefines how elements look and function




http://slidepdf.com/reader/full/aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf 7/361-7

Programming Languages-Procedural,Event Driven and Object Oriented

Procedural —Cobol, Fortran, BasicProgram specifies exact sequence of all operations

Event Driven (VB 6.0 and previous)Contain some elements of Object oriented programming but not all

Object Oriented Programming (OOP) (VB .NET)User controls sequence

Click eventDouble Click eventChange event



The Object Model (1 of 2)

In VB you will work with objects, which have properties,methods, and events. Each object is based on a class.Objects equate to Nouns

Forms are windowsControls are components contained inside a form

Properties equate to AdjectivesColor or size of a Form

Methods are like VerbsTypical methods include Close, Show and Clear



Object Model (2 of 2)

Events occur when the user takes actionUser clicks a button , User moves a form

Classes are templates used to create a new objectClasses contain the definition of all available properties,methods, and eventsEach new object created is based on a class

Creating three new buttons makes each button a instanceof the Button class



Object Model Analogy

Class = automobileProperties = make, model, color, year Object = each individual car

Object is also an Instance of the automobile class

Methods = start, stop, speedup, slowdownEvents = car arrives, car crashes



Visual Studio .NET

Included in Visual Studio .NET 2005Visual Basic (can also be purchased separately)Visual C++

C# (C sharp)J# (J sharp).NET 2.0 Framework

Visual Studio .NET Editions

StandardProfessionalEnterprise Developer Enterprise Architect



Writing Visual Basic Projects

There is a three-step process when writing a Visual Basicapplication—you set up the user interface , define theproperties and then create the codePlanning

1. Design the User Interface2. Plan the Properties3. Plan the Basic Code; follow the language syntax rules; use

pseudocode (English expression or comment describing

action) then you move on toProgramming (and use the same three step process)

1. Define the User Interface2. Set the properties3. Write the Basic code



VB Application Files

One Solution File—think of one solution file equals one project .sln

Solution User Options File .suo

Form Files .vbResource File for the Form .resx

Project Files .vbproj

Project User Options File .vbproj.user

Application configuration File .app.config

Once a project is run several more files are created by thesystem. The only file that is opened directly is the solution file.



Visual Studio Environment

The Visual Studio environment is where you create andtest your projects-in Visual Studio it is called anIntegrated Development Environment (IDE)

consists of various tools including:Form Designer Editor for entering codeCompiler Debugger Object Browser Help facility



Default Environment Settings

Visual Studio 2005provides a new option

that allows theprogrammer to select thedefault profile for the IDE



The IDE Initial Screen

The VisualStudio IDE withthe Start Page

open, as it firstappears inWindows XP,without an openproject.



1-17

IDE Main Window

ToolbarsDocument WindowForm Designer Solution Explorer Window Properties WindowToolboxHelp



1-18

ToolBox

You can scroll to view morecontrolsTo sort the tools in thetoolbox:

•Right-click the toolbox andselect•Sort Items Alphabetically

from the context menu (shortcut menu).



1-19

Modes

Design Time--used when designing the user interfaceand writing codeRun Time--used when testing and running a project

Break Time- -if/when receiving a run-time error or pause error

“Look at the Title Bar”



1-20

Writing Your First Visual Basic ProjectSetting Up the Project

1

2

3

Hello World Project



1-21

Planning the Project

Design the user interfaceSet up the form

Resize the form

Place a label and a buttoncontrol on the form using thetoolbox

Lock the Controls in place

After the user interface isdesigned, the next step is toset the properties



1-22

Setting Properties

Label 1Name messageLabelText leave blank

Button 1

Name pushButtonText Push Me

Button 2Name exitButtonText Exit

FormName helloFormText Hello World by

your name



1-23

Setting the Form Properties

The default startupobject is Form1The name of the form

should always bechanged to adhere tonaming rulesThe properties window

shows the files properties



1-24

Writing the Code

While the project is running the user can performactionsEach action by the user causes an event to occur Write code for the events you care about; the

events you want to respond to with codeCode is written as event proceduresVB will ignore events for which you do not write

codeVB will automatically name event procedures asthe object name, an underscore(_) and the name of the event



1-25

More on Writing the Code

When writing the code for your first project you willuse the following:

Remark Statement

Assignment StatementEnding a ProgramEditor Window



1-26

' Display the Hello World message.

Remark Statement

Also known as Comment, used for documentation; every procedure should beginwith a remark statement providing explanation

Non-executableAutomatically colored Green in Editor Begins with an apostrophe ( ' )

On a separate line from executable codeAt the right end of a line of executable code



1-27

messageLabel.Text=" Hello World "

Assignment Statement

Assigns a value to a property or variableOperates from right to left- the value appearing on the

right side of the equal sign is assigned to the property

named on the left of the equal signEnclose text strings in quotation marks (" ")



1 28

Ending a Program

Methods always have parentheses (this will help youdistinguish them from Properties which never have parentheses)

To execute a method of an object you write:

Object.Method()Current Form may be referenced as Me

Me.Close( )



1 29

Editor Window

Declarations SectionClass listMethod list

d f b d



1 30

Run, Save, Modify, Print, Test, Debug andExecute

Run ProjectDebug Menu, StartStart (F5)

Start Without Debugging (CTRL+F5)

Save Project - File Menu, Save AllModify Project if neededPrint the CodeCorrect any Errors and Rerun

When you start executing your program, the first step iscalled compiling , which means that the VB statements areconverted to Microsoft Intermediate Language (MSIL). Your goal is to have no errors during the compile process: a

l il

"Help is always available from theHelp Menu or by pressing F1."



1 31

Print the Code

File Menu, PrintPrints complete code listingUses arrow symbol to denote line continuation



1 32

Finding and Fixing Errors

Syntax ErrorsBreaks VB’s rules for punctuation, format or spellingSmart editor finds most syntax errors, compiler finds the restThe editor identifies a syntax error with a squiggly blue line

and you can point to an error to pop up the error message.You can display the Error List window and line numbers in thesource code to help locate the error lines.

Run-Time Errors

Statements that fail to execute such as impossible arithmeticoperations

Logic ErrorsProject runs but produces incorrect results



1 33

Naming Rules and Conventions

Have a set of standards and always follow themNo spaces, punctuation marks or reserved words

Use camel casingExamples

messageLabelexitButton

dataEntryFormpaymentAmountTextBox

R d d N i g C ti f



1 34

Recommended Naming Conventions for VB Objects

Object Class Example

Form dataEntryForm

Button exitButton

Label totalLabel

TextBox paymentAmountTextbox

Radio button boldRadiobutton

CheckBox printSummaryCheckBox

Horizontal Scroll Bar rateHorizontalScrollBar

Vertical Scroll Bar temperatureVerticalScrollBar

PictureBox landscapePictureBox

ComboBox bookListComboBox

ListBox ingredientsListBox

SoundPlayer introPageSoundPlayer



1 35

Visual Studio Help Additional Info (1 of 2)

Visual Studio has an extensive Help facility,Filter MSDN help to display VB topics onlyRun MSDN from hard drive, CD or Web

You can access MSDN on the Web athttp://msdn.microsoft.com

The Help system display is greatly changed and

improved in Visual Studio 2005. You view the Helptopics in a separate window from the VS IDE, so youcan have both windows open at the same time .

http://msdn.microsoft.com/

http://msdn.microsoft.com/



1 36

Visual Studio Help Additional Info (2 of 2)

When you choose How Do I , Search , Contents ,Index , or HelpFavorites from the Helpmenu, a new window

opens on top of theIDE window. You canswitch from onewindow to the other, or resize the windows toview both on thescreen if your screen islarge enough.

Documents

Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf Aslkjdhfalskhjfgalsdkfhalskdhjfglaskdhjflaskdhjfglaksjdhflakshflaksdhjfglaksjhflaksjhf