VB Basic Syntax


VB.Net is an object-oriented programming language. In Object-Oriented Programming methodology, a program consists of various objects that interact with each other by means of actions. The actions that an object may take are called methods. Objects of the same kind are said to have the same type or, more often, are said to be in the same class.

When we consider a VB.Net program, it can be defined as a collection of objects that communicate via invoking each other's methods. Let us now briefly look into what do class, object, methods and instant variables mean.

  • Object - Objects have states and behaviors. Example: A dog has states - color, name, breed as well as behaviors - wagging, barking, eating, etc. An object is an instance of a class.
  • Class - A class can be defined as a template/blueprint that describes the behaviors/states that object of its type support.
  • Methods - A method is basically a behavior. A class can contain many methods. It is in methods where the logics are written, data is manipulated and all the actions are executed.
  • Instant Variables - Each object has its unique set of instant variables. An object's state is created by the values assigned to these instant variables.

Identifiers

An identifier is a name used to identify a class, variable, function, or any other user-defined item. The basic rules for naming classes in VB.Net are as follows:

  • A name must begin with a letter that could be followed by a sequence of letters, digits (0 - 9) or underscore. The first character in an identifier cannot be a digit.
  • It must not contain any embedded space or symbol like ? - +! @ # % ^ & * ( ) [ ] { } . ; : " ' / and \. However, an underscore ( _ ) can be used.
  • It should not be a reserved keyword.

VB.Net Keywords

The following table lists the VB.Net reserved keywords:

AddHandler AddressOf Alias And AndAlso As Boolean
ByRef Byte ByVal Call Case Catch CBool
CByte CChar CDate CDec CDbl Char CInt
Class CLng CObj Const Continue CSByte CShort
CSng CStr CType CUInt CULng CUShort Date
Decimal Declare Default Delegate Dim DirectCast Do
Double Each Else ElseIf End End If Enum
Erase Error Event Exit False Finally For
Friend Function Get GetType GetXML Namespace Global GoTo
Handles If Implements Imports In Inherits Integer
Interface Is IsNot Let Lib Like Long
Loop Me Mod Module MustInherit MustOverride MyBase
MyClass Namespace Narrowing New Next Not Nothing
Not Inheritable Not Overridable Object Of On Operator Option
Optional Or OrElse Overloads Overridable Overrides ParamArray
Partial Private Property Protected Public RaiseEvent ReadOnly
ReDim REM Remove Handler Resume Return SByte Select
Set Shadows Shared Short Single Static Step
Stop String Structure Sub SyncLock Then Throw
To True Try TryCast TypeOf UInteger While
Widening With WithEvents WriteOnly Xor

Share this article on