VB'Net Basics

1
VB.Net Basics

• ITE 285

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Forms and Controls

• __________ Visual Object that is the basis of the
  User Interface
• Call a Window at __________
• Contains the __________
• __________ Object places on the form to enable
  customizable activities
• Visual (most)
• Display some information
• Allow the user to __________ with program

3
Objects

• One of the most basic elements of the VB Program
• Objects Have
• __________
• __________
• __________

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Object Properties

• Determine an objects __________ (and sometimes
  behavior)
• Text Field
• Visible
• Font
• BorderStyle
• Enabled

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Object Events

• An action initiated by the user or the operating
  system that the program can respond to
• Basis of Event Driven Programming
• Events are __________
• When Fired, __________ will execute
• Each Event is Associated with a __________

6
Object Methods

• __________ that performs a task relative to a
  specific object
• Things the objects already know how to do
• Show
• SetFocus

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Designing a GUI

• Form the on screen window your program owns
• TOE Chart __________ , __________ , __________
• Task your interface helps user perform
• Object the VB control you will use
• Fired Event for which you will write code to
  respond. May be N/A.
• Also dont forget a simple sketch!!!

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TOE Chart
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Form

• Part of the Windows Forms Class
• Container for __________
• Always orient a forms as defined by the
  __________

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Form Properties

• Prefix __________
• Text
• Start Position
• Size.Width
• Location.X, Location.Y
• FormBorderStyle
• Visible
• Enabled

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Form Methods

• Form1.Show()
• Form1.ShowDialog()
• Form1.Close()
• Form1.Hide()

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Form Events

• Form1_Load()
• Form1_Activated()
• Form1_Deactivated()

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Command Button

• Task __________
• Common Properties
• __________ (the variable name)
• __________ (what is displayed)
• Prefix __________
• Click event procedure where you put code.

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Textbox

• Task __________
• Common Properties
• Name, Text
• TextAlign, Readonly
• CharacterCasing
• Multiline
• Prefix __________

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Label

• Task __________ __________ __________ __________
  
• Common Properties
• Name, Text
• UseMnemonic
• Prefix __________ non-default name only needed
  if you use at runtime

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Checkbox

• Task __________ __________
• Common Properties
• Name, Text
• Checked (a boolean)
• Prefix __________

17
Radiobutton

• Task __________ __________ __________ __________
  
• Common Properties
• Name, Text
• Checked
• Prefix __________
• Usually with Groupbox

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Groupbox

• Purpose
• __________ __________ __________
• Define a set of radiobuttons
• Common Properties
• Prefix __________

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Best Control

• __________ __________
• __________ __________
• __________ __________
• __________ __________

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More on Properties

• We will be using many other properties of these
  controls!!

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Not in the Toolbox

• __________
• __________
• Similar to JOptionPane dialogs in Java
• Only use on exceptional basis!!!!!

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Keyboard Issues

• Focus
• __________ __________ __________ __________
• Focus is advanced to next control by mouse click
  on it or pressing the Tab key.
• Tab Order
• __________ __________ __________.
• Edit order interactively ViewgtTab Order
• Or TabIndex property of each control.
• Access Keys
• __________ in Text value works with Alt- as a
  keyboard shortcut

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VB.Net IDE

• IDE __________ __________ __________
• Contains source code editor, compiler, debugger,
  help.
• Similar in concept to JGrasp or Eclipse.

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New Project Dialog

• Make sure you set the location __________ _____
• Name is used for new folder as well as files.

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Project Workspace w/Form
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Toolbox

• Place control on Form
• __________
• __________
• Click in toolbar if hidden
• Your controls are objects, instances of the
  control class.

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Properties

• If hidden
• AZ button sorts alphabetically
• Click in value field for button to see predefined
  list

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Writing Code

• When using the Design view to add controls and
  adjust Properties, code is written for you.
• Add your code in Code View
• __________ __________ __________ __________
  __________ __________ __________ __________
• Can switch views with tabs at top
• Most of our code for now will be in Event
  procedures

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Compiling and Running

• Build menu compiles and links
• Running
• __________ _______
• Play button in toolbar.
• F5

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Build __________ Errors

• ALWAYS click No on a build error!
• Task List at bottom left will show error msg.
  
• Dbl-click msg to highlight suspected line of code
  in source window.

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Solution Explorer

• __________ __________ from the default Form1 to
  something like frmMain (in Properties).
• Next, rename the file the same, eg frmMain.vb
• Set the projects __________ to the new name
  (menu ProjectgtProperties)

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Project FilesDefault location is underMy
DocumentsgtVisual Studio ProjectsgtYourProjectName
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Project Files 2

• You can load project by dbl-clicking Project
  (.vbproj) or Solution (.sln) file.
• The compiled executable (.EXE) is in the
  __________ .
• NEVER save files to a floppy using FilegtSaveAs
  from inside Visual Studio!
• Always save everything, exit VS, then copy entire
  project folder.

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VB.Net Language Basics
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Comments

• Comments are text we want __________
  are NOT executable statements
• VB comments indicated with single-quote
  (apostrophe) and are green in IDE
• I expect comments for identifying yourself,
  assignment, purpose, and elsewhere for clarity
• Older code may use REM (remark)

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Variable Declarations

• Associate a variable name to be used with a data
  type
• Form __________
• May have Const, Private or Public instead of Dim
• Initialize Dim strName As String Joe
• __________ __________ IDE keeps case consistent
  w/ declaration

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VB.Net Data Types
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Literal Values

• 4 Integer
• 4.24 Double
• John String
• y Char from context
• 3/1/2006 Date

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Operators

• Assignment
• Arithmetic
• Relational (comparison)
• Logical
• Dot operator

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Assignment

• The __________ serves as the Assignment Operator
• In an expression such as yy1
• Right hand side is evaluated
• Result is copied to left hand side variable

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Arithmetic Operators

• Addition
• - Subtraction
• Multiplication
• / Division
• \ Integer Division
• Mod Modulus or remainder (like Java )
• __________ __________ is similar to Java, ( ) to
  override it.

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Relational Logical Operators

• Equality test with __________ (not )
• Not Equal __________ instead of !
• gt, lt, gt, lt just like Java
• __________ instead of
• __________ instead of
• __________ instead of !

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Calling Procedures

• A __________ is like a Java method
• __________ (short for subroutine) is like a Java
  void method.
• A Sub call is always a standalone statement.
• __________ is like a Java method that returns a
  result that replaces the call in the larger
  expression.

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Event Handling Procedures

• For now we write most of our code in Event
  Handling Procedure Subs.
• Similar to Java __________
• We never call these directly
• Instead .NET passes event from interface, calling
  our Event Handler Sub when needed.
• __________ event list can respond to more than
  one event.

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Built-In Functions

• Many functions follow OOP paradigm
• string methods, e.g. Name.IndexOf(i)
• Math functions e.g. Math.Sin(x)
• __________ functions are standalone
• Val(mystring), CDbl(mystring), CInt(mystring)
• IsNumeric( mystring)
• FormatNumber(x, 2)
• Financial functions, random numbers