An Overview of Visual Basic .NET
Overview-An Overview of Visual Basic .NET
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Methods of Programming
 Procedural Languages
 Constructed as a set of procedures
(operational, functional units)
 Often used in text-based environments
 Object-Oriented
 Constructed as a set of objects
 Objects have data elements (i.e. properties) and
perform actions (i.e. methods)
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Object-Oriented/Event-Driven
Languages
 Simplifies the task of programming GUI
applications.
 In object-oriented/event-driven languages, the
emphasis of a program is on the objects included
in the user interface (such as scroll bars and
buttons) and the events (such as scrolling and
clicking) that occur when those objects are used
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OOP Terminology
 OOP is an acronym for object-oriented
programming
 It means that you are using an object-oriented
language to create a program that contains one or
more objects
 OOD is an acronym for object-oriented design
 Like top-down design, which is used to plan
procedure-oriented programs, OOD is also a
design methodology, but it is used to plan objectoriented programs
 OOD divides a problem into one or more objects
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Object
An Object:
 Is Anything that can be seen or touched
 Has attributes (properties) that describe it
 Has behaviors(events) that the object can
either perform or have performed on it
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Types of Controls
Ch1\Program2 on p.10
(This application can be found in the student data files)
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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, C# .NET and J#
 Can Create:
 A Windows-based application has a Windows user
interface and runs on a desktop computer
 A console application
 A Web-based application, on the other hand, has a
Web user interface and runs on a server
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Overview-An Overview of Visual Basic .NET
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.NET Framework
New Concepts

Common Language Runtime (CLR)



Execution engine
Memory management
Intermediate Language (IL)


VB.NET compiles to IL
Just-in-time compilation
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Language Interoperability
.NET: Type System
Standard
C#
Overview-An Overview of Visual Basic .NET
VB.NET
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The Programming Process
(1.5)
The Programming Process Consists of Several
Steps, Which Include Design, Creation, Testing,
and Debugging Activities
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Example of an Object
 This is a GUI object
 Data includes number-ofhours-worked, hourly-payrate, and gross-pay-earned
 Action is to calculate and display gross-payearned, given number-of-hours-worked and
hourly-pay-rate
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Step 1 of Developing an Application
 Clearly define what the program is to do
 For example:
 Purpose: To calculate the user’s gross pay
 Input: Number of hours worked, hourly pay rate
 Process: Multiply number of hours worked by hourly
pay rate (The result is the user’s gross pay)
 Output: Display a message indicating the user’s gross
pay
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Step 2 of Developing an Application
 Visualize the application running on the computer and
design its user interface
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Step 3 of Developing an Application
 Make a list of the controls needed
 Partial list:
Type
TextBox
TextBox
Label
Name
txtHoursWorked
txtPayRate
lblGrossPay
Button
btnCalcGrossPay
Button
btnClose
Overview-An Overview of Visual Basic .NET
Description
Allows the user to enter the number of hours worked.
Allows the user to enter the hourly pay rate
Displays the gross pay, after the btnCalcGrossPay
button has been clicked
When clicked, multiplies the number of hours worked
by the hourly pay rate
When clicked, terminates the application
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Step 4 of Developing an Application
 Define the Values of Each Control's Relevant Properties:
Control Type
Form
Label
Label
Label
Label
TextBox
TextBox
Button
Button
Control Name
(Default)
(Default)
(Default)
(Default)
lblGrossPay
txtHoursWorked
txtPayRate
btnCalcGrossPay
btnClose
Overview-An Overview of Visual Basic .NET
Text
"Wage Calculator"
"Number of Hours Worked"
"Hourly Pay Rate"
"Gross Pay Earned"
"$0.00"
""
""
"Calculate Gross Pay"
"Close"
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Step 5 of Developing an Application
 Make a list of methods needed for each control:
Method
Description
btnCalcGrossPay_Click Multiplies the number of hours worked by the
hourly pay rate
These values are entered into the
txtHoursWorked and txt-PayRate TextBoxes
The result is stored in the lblGrossPay Text
property
btnClose_Click
Terminates the application
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Step 6 of Developing an Application
 Create a pseudocode version of each method:
 Pseudocode is a combination of English and a
programming language
 For this application:
Store Number of Hours Worked times
Pay Rate in grossPay.
Store the value in grossPay in
lblGrossPay.Text.
Overview-An Overview of Visual Basic .NET
Hourly
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Step 7 of Developing an Application
 Check the code for errors:
 Go step by step through the code, running it in your
head as though the computer is running it
 Keep track of where in the code is being executed
 Keep track of the values of all of the variables
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Step 8 of Developing an Application
 Use Visual Basic .NET to create the forms and other
controls identified in step 3
 This is the first use of Visual Basic .NET, all of the
previous steps have just been on paper
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Step 9 of Developing an Application
 Use Visual Basic .NET to write the code for the event
procedures and other methods created in step 6
 This is the second step on the computer
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Step 10 of Developing an Application
 Attempt to run the application - find syntax errors
 Correct any syntax errors found and repeat this step as
often as necessary
 All of the syntax errors must be removed before Visual
Basic .NET will create a program that you can actually
run on the computer
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Step 11 of Developing an Application
 Run the application - once all syntax errors are fixed
 Run the program with a variety of test data
 Check the results to be sure that they are correct
 Correct any errors found
 Repeat steps 10 and 11 as many times as necessary
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Visual Studio .NET
Recent Projects
Toolbox
Overview-An Overview of Visual Basic .NET
Solution
Explorer
Dynamic
Help
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Starting a New Project
Installed .NET
Products
Name and Location
Of Project
Overview-An Overview of Visual Basic .NET
Type of
Project
Name of
Project
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Toolbox
(autohidden)
Visual Basic .NET
Project
information
Windows
Form object
Overview-An Overview of Visual Basic .NET
Properties
window
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The Visual Basic .NET Environment




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
Design Window
Solution Explorer Window
Dynamic Help Window
Properties Window
Docked and Floating Windows
Toolbox
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