What is vb.net / PDF
BASIC –
Beginner’s All-Purpose Symbolic Instruction Code
Developed in the
mid 1960s by Kemeny and Kurtz at Dartmouth
Designed to be a
language for novices
Became the
standard language for early PCs
For Windows to
be successful, MS needed a language to easily create Windows apps
Began as a shell
language for interface design (Alan Cooper’s “Tripod”)
Renamed “Ruby”
it was intended as a part of Windows 3.0 but dropped
Later became
known as “Thunder” and is considered the first RAD tool
Bill Gates had apparently promised a BASIC language compiler so that
became the base for the language
VB1 was
introduced in May 1991 at Windows World Conference
VB3 allowed
database support and that made the language much more popular
VB .Net has moved
to an object-oriented version
Find more info
at: http://msdn.microsoft.com/vbasic/bday/default.asp
How
does Visual Basic differ from C++ and Java?
First,
the languages themselves are quite different
different syntax
Java and
C++ are object-oriented and VB is too (but only with VB .Net)
As with C++, VB does not force you to do OO
programming
Visual
Basic is designed for only one platform – to create Windows-based applications
there is no Mac or Unix version of VB
fortunately, for Microsoft and VB programmers,
we live in a Windows world
Visual
Basic has only one vendor - Microsoft
there are no competing versions of VB
available from other companies
nothing around is even similar (Delphi might
be the closest)
Java is in the public domain and changes are
managed
Visual
Basic for Applications is a closely related language used within Office for
macros
also now used by WordPerfect and Visio
latest version is a bit faster and offers
better security
other products are adopting it as well
but VBA is more like VB6 than like VB .Net
What will happen with the upcoming VBA is
still uncertain
Visual
Basic Script is also used for Internet applications
But
this is not the same as Visual Basic (even earlier versions)
What is .Net?
The .Net framework is more than just the
latest version of Visual Basic
Visual Studio .Net includes C++, C# and VB
(a version of Java is to be added later)
Consistent IDE
(Integrated Development Environment) across these languages
Different
languages can be easily used in a single application
Also supported
by versions of APL, COBOL, Fortran, Pascal, Smalltalk, Python
This has some major implications for
development
programmers can
work in whatever language they prefer or know best
code written in
one language can be easily integrated later (i.e., reused)
The .Net architecture is planned to exist
on multiple platforms
different
hardware and operating systems
this includes
other devices such as PDAs and even cell phones
Designed for the Web (topic to be covered
in a new course)
Getting
Started with Visual Basic
Opening a Visual Basic Project
From the Start
menu, click on New Project
Then select
Visual Basic Projects (left side) and Windows application (right)
Change the name
to something more meaningful (e.g., TestProgram)
Change the location
(path)
Show the Visual Basic Integrated
Development Environment (IDE)
Menus (View
Toolbar, Standard and Layout are normally checked)
Form
Toolbox
Solution
Explorer
Properties
Code (editor)
If any of these features are missing, they
can be restored using the View menu
Form (Design Mode)
unlike most
older languages, what you see is not a screen for text entry of code
the empty Form
on the screen will become the Form the user sees
Forms have Properties (should be displayed
in the bottom right hand corner)
Change the
BackColor
There are three
options – Custom, Web and System
Web and System
are set to match the Windows settings of a particular computer
This is great if
you want your program to follow the user’s settings
But not good if
you want fixed colors
Normally, a
BackColor will come from Custom
Add a few controls from the Toolbox to
create interface objects
Single-click a
control and then use the mouse to draw it on the screen
Double-click and
it will appear in the top left corner
Unless you already
have another control selected
Running a VB program
To run the program (any of these will work)
From the menu,
Debug / Start
F5 shortcut key
The Form should now be displayed in its own window
This may not look like much but a lot has
already happened
a Window has
been created on the screen with a border
its size and
color are determined
it has a
TitleBar with an icon and caption (Form1)
it has buttons
in the top right corner for minimizing, resizing and closing the Form
and they all
work!
Some of this has been created as code for
you automatically (you can see the code later)
Other parts are built in to VB and happen
in the background
just like most
languages calculate square roots
you use a
function call and never see the code that makes it work.......
what is vb.net / PDF
0 commentaires: