MaximumPC 2004 09

NO

The newly born Windows

Form, future home of our

GUI. Simple. Unassuming.

Gray. Very gray.

Windows Application on
the right of the dialog
box under the Templates
label. For simplicity’s sake,
we’ll call our program
“MaxPC02.” Once you click
the OK button, VS2003 will
create a new directory in
the My Documents\Visual
Studio Projects folder. This
directory will have the
same name as your proj-
ect and will contain all the
files that make up your
application.
The IDE has now entered the
WYSIWYG design view mode, and a
blank Windows Form named Form1
has been created. Look at the Solution
Explorer and you’ll see that the file rep-
resentation of Form1, named Form1.vb,
has been created as well. Form1 is our

GUI for this project, and will be the

canvas on which we create our pro-

gramming masterpiece. Form1 is

a lousy moniker for a work of art,

though, so let’s change it. In the

process, you’ll learn more about

the Visual Studio IDE as well as

Windows Forms.

SEPTEMBER 2004 MA XIMUMPC 67

The journey of a thousand miles begins with the

creation of a new VB.NET project.

Stepping through a GUI

From the time your program’s first form loads to the time it exits, this chart shows you every function

YES

NO

YES

(Cryptography.Decrypt)

Decrypt text

(ValidateKey)

Program

validates

key

Form1 exits

(btnExit_Click)

Exit button clicked

(Cryptography.Encrypt)

Encrypt text

(btnEncrypt_Click)

Encrypt button

clicked

(btnDecrypt_Click)

Decrypt button

clicked

The user starts the application

and Form1 loads into memory

When the Exit button is

clicked the btnExit’s click

event is triggered.

If the user has entered a valid key,

either the Decrypt or Encrypt method

is called. If an invalid key is entered,

neither method is called and the user

is presented with an error.

Once btnExit’s click is triggered, the application terminates.

Form1 loads

The application is ready

for use and waits for

input from the user.

Form1

The user clicks the Decrypt

button, which triggers

btnDecrypt’s click event. btn-

Decrypt’s click function starts

the ValidateKey function.

The function

that handles

the actual

encryption of

the text the

user entered.

The Encrypt button is

clicked and btnEncrypt’s

click event is raised.

(ValidateKey)

Program

validates

key

The function that

handles the actual

decryption of the

text the user

entered.