Introduction to Visual Basic and the VB IDE

1
Introduction to Visual Basicand the VB IDE
2
Motivation

• We'd like to be able to write programs that will
  run on Windows
• We'd like to use Rapid Application Development
  methods
• Were interested in developing object-oriented,
  event-driven applications

3
Basic

• 10 sum 0
• 20 FOR i 1 to 100
• 30 sum sum i
• 40 NEXT i
• 50 avg sum / 100
• 60 PRINT "The average is " avg
• 70 END

4
RAD

• Rapid Application Development
• Easily develop interface prototypes
• Accelerates delivery of system
• Better user feedback and testing
• WYSISYG development

5
Object-oriented Programming

• Think in real-world concepts
• Objects have
• Properties/attributes (nouns)
• Actions/events (verbs)
• Akin to a "record" on steroids! ?
• Groups data and procedural abstraction together
• Provides for encapsulation information hiding

6
Event-Driven Programming

• Basic and Pseudocode run from top to bottom
• Main program/algorithm in control
• Event-driven programs respond to events
• Usually graphical (forms, buttons, controls)
• Instructions are executed in response to events
• Button press, control change, form close, etc.

7
Anatomy of a VB Program
Form
Controls
User clicks on the cmdBorder button
A Click() event is generated
The cmdBorder_Click() method is executed
8
Event-drivenvs. Procedural
algorithm CalcAges // create the 4 age
variables Age1, Age2, Age3, Age4 isoftype Num
// prompt the user and then read in the //
numbers print("Please enter 4 ages")
read(Age1, Age2, Age3, Age4) // I need a
place to store the average avg isoftype Num
// calc the average avg lt- (Age1 Age2
Age3 Age4) / 4 // display it back to the
user print("The average age is ", avg)
endalgorithm
9
VB Program Development

• Design
• Create the User Interface (UI)
• Set form and control properties
• Code event handlers
• Save and test/debug your program often!
• Create executable file
• Create setup program(for deployment on other
  computers)

10
The VB IDE
Project Explorer
Form Designer
Toolbar
Properties Editor
Code Editor
11
Design vs. Run Time

• Design time
• When youre building your program
• Some properties may not be set
• Run time
• When you run your program
• Events are generated from user (buttons, etc.)
• Opens up more properties of controls

12
Versions and Editions

• Visual Basic has evolved and will continue to
  evolve
• Were using VB 6.0 (from Visual Studio 6.0
  Enterprise)
• VB7.0 (or VB.Net) is forthcoming and in BETA now
• Different levels/editions available
• Learning (standard controls, samples, ADO DB
  support)
• Professional (additional controls,
  Internet/client-server)
• Enterprise (SourceSafe, IIS, SQL)

13
File Types

• VBP Visual Basic Project (meta file)
• VBW Visual Basic Workspace (settings of
  project)
• FRM Form (form, control, methods, attributes)
• EXE Self-contained executable program
• SCC Visual SourceSafe file (for
  versioning/collaboration)
• others to be announced as needed

14
MSDN

• Microsoft Developers Network
• Your lifeline
• Your best friend when programming
• On-line or on CD-Rom
• http//www.msdn.microsoft.com
• Mouse over Libraries and click MSDN
  Libraries
• Live it Love it Use it!

15
Summary

• VB is based on Basic
• VB is a RAD language
• VB is an event-driven language
• VB is an object-oriented language
• VB comes in different versions and editions
• Important terms to know/understand
• Form, control, method, event, attribute/property
• IDE, RAD, OOP

16
(No Transcript)