ComparisonofVBandC#.pdf

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Posted 30 Mar 2005 14:53

Updated 18 Apr 2005 9:26

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Complete Comparison for

VB.NET and C#

By Amalorpavanathan Yagulasamy(AMAL)

This article explains about advantages, differences and new

features of VB.NET and C#.

47 members have rated this article. Result:

Popularity: 7.49 . Rating: 4.48 out of 5.

Contents

1. Introduction

2. Advantages of both languages

3. Keyword Differences

4. Data types Differences

5. Operators Differences

6. Programming Difference

7. New Features of both languages in 2005 version

8. Conclusion

9. History

Introduction

Some people like VB.NET's natural language, case-insensitive approach, others like

C#'s terse syntax. But both have access to the same framework libraries. We will

discuss about the differences in the following topics:

1. Advantages of both languages

2. Keyword Differences

3. Data types Differences

4. Operators Differences

5. Programming Difference

Advantages of both languages

VB.NET

Support for optional parameters - very

handy for some COM interoperability.

XML documentation generated

from source code comments. (This

is coming in VB.NET with Whidbey

(the code name for the next

version of Visual Studio and .NET),

and there are tools which will do it

with existing VB.NET code

already.)

Support for late binding with Option

Strict off - type safety at compile time

goes out of the window, but legacy

libraries which don't have strongly typed

interfaces become easier to use.

Support for named indexers.

Various legacy VB functions (provided in

the Microsoft.VisualBasic

namespace, and can be used by other

languages with a reference to the

Microsoft.VisualBasic.dll ). Many of these

can be harmful to performance if used

unwisely, however, and many people

believe they should be avoided for the

most part.

Operator overloading - again,

coming to VB.NET in Whidbey.

Language support for unsigned

types (you can use them from

VB.NET, but they aren't in the

language itself). Again, support for

these is coming to VB.NET in

Whidbey.

The using statement, which

makes unmanaged resource

disposal simple.

The with construct: it's a matter of

debate as to whether this is an

advantage or not, but it's certainly a

difference.

Explicit interface implementation,

where an interface which is

already implemented in a base

class can be re-implemented

separately in a derived class.

Arguably this makes the class

harder to understand, in the same

way that member hiding normally

does.

Simpler (in expression - perhaps more

complicated in understanding) event

handling, where a method can declare

that it handles an event, rather than the

handler having to be set up in code.

The ability to implement interfaces with

methods of different names. (Arguably

this makes it harder to find the

implementation of an interface,

however.)

Unsafe code. This allows pointer

arithmetic etc, and can improve

performance in some situations.

However, it is not to be used

lightly, as a lot of the normal

safety of C# is lost (as the name

implies). Note that unsafe code is

still managed code, i.e., it is

compiled to IL, JITted, and run

within the CLR.

Catch ... When ... clauses, which allow

exceptions to be filtered based on

runtime expressions rather than just by

type.

The VB.NET parts of Visual Studio .NET

compiles your code in the background.

While this is considered as an advantage

for small projects, people creating very

large projects have found that the IDE

slows down considerably as the project

gets larger.

Keyword Differences

Purpose

VB.NET

Declare a variable

Private , Public , Friend ,

Protected , Static1 ,

Shared , Dim

declarators (keywords include

user-defined types and built-in

types)

Declare a named

constant

Const

const

Create a new object New , CreateObject()

new

Function/method

does not return a

value

Sub

void

Overload a function

or method (Visual

Basic: overload a

procedure or

method)

Overloads

(No language keyword required for

this purpose)

Refer to the current

object

this

Make a nonvirtual

call to a virtual

method of the

current object

MyClass

n/a

Retrieve character

from a string

GetChar Function

[]

Declare a compound

data type (Visual

Basic: Structure)

Structure <members> End

Structure

struct , class , interface

Initialize an object

(constructors)

Sub New ()

Constructors, or system default type

constructors

Terminate an object

directly

n/a

Method called by the

system just before

garbage collection

reclaims an object7

Finalize

destructor

Initialize a variable

where it is declared

Dim x As Long = 5

// initialize to a value:

int x = 123 ;

// or use default

// constructor:

int x = new int ();

Dim c As New _

Car(FuelTypeEnum.Gas)

Take the address of

a function

AddressOf (For class

members, this operator

returns a reference to a

function in the form of a

delegate instance)

delegate

Declare that an

object can be

modified

asynchronously

n/a

volatile

Force explicit

declaration of

variables

Option Explicit

n/a. (All variables must be declared

prior to use)

Test for an object

variable that does

not refer to an

object

obj = Nothing

obj == null

Value of an object

variable that does

not refer to an

object

Nothing

null

Test for a database

null expression

IsDbNull

n/a

Test whether a

Variant variable has

been initialized

n/a

Define a default

property

Default

by using indexers

Refer to a base class MyBase

base

Declare an interface

Interface

interface

Specify an interface

to be implemented

Implements (statement) class C1 : I1

Declare a class

Class <implementation> class

Specify that a class

can only be

inherited. An

instance of the class

cannot be created.

MustInherit

abstract

Specify that a class

cannot be inherited

NotInheritable

sealed

Declare an

enumerated type

Enum <members> End Enum enum

Declare a class

constant

Const

const (Applied to a field

declaration)

Derive a class from

a base class

Inherits C2

class C1 : C2

Override a method

Overrides

override

Declare a method

that must be

implemented in a

deriving class

MustOverride

abstract

Declare a method

that can't be

overridden

NotOverridable (Methods

are not overridable by

default.)

sealed

Declare a virtual

method, property

(Visual Basic), or

property accessor

(C#, C++)

Overridable

virtual

Hide a base class

member in a derived

class

Shadowing

n/a

Declare a typesafe

reference to a class

method

Delegate

delegate

Specify that a

variable can contain

an object whose

events you wish to

handle

WithEvents

(Write code - no specific keyword)

Specify the events

for which an event

procedure will be

called

Handles (Event procedures

can still be associated with a

WithEvents variable by

naming pattern.)

n/a

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