Vb and c# Comaprison

8/11/2019 Vb and c# Comaprison

1/16

Comments

VB.NET

'Single line only

RemSingleline only

C#

// Single line

/* Multipleline *//// XML comments on single line

/** XML comments on multiple lines */

Program Structure

VB.NET

ImportsSystem

NamespaceMyNameSpace

ClassHelloWorld

'Entry point which delegates to C-style mainPrivate Function

PublicOverloadsSharedSubMain()

Main(System.Environment.GetCommandLineArgs())

EndSub

OverloadsSharedSubMain(args() AsString)System.Console.WriteLine("Hello World")

EndSub'Main

EndClass'HelloWorld End Namespace'MyNameSpace

C#

usingSystem

Namespace MyNameSpace

{

classHelloWorld

{staticvoidMain(string[] args)

{

System.Console.WriteLine("HelloWorld")

}

}}


2/16

Data Types

VB.NET

'Value TypesBoolean

ByteChar(example: "A")

Short, Integer, LongSingle, Double

Decimal

Date

'Reference Types

ObjectString

Dimx AsInteger

System.Console.WriteLine(x.GetType())

System.Console.WriteLine(TypeName(x))

'Type conversion

Dimd AsSingle=3.5

Dimi AsInteger=CType(d, Integer)i =CInt(d)

i =Int(d)

C#

//Value Typesbool

byte, sbytechar(example: 'A')

short, ushort, int, uint, long, ulongfloat, double

decimal

DateTime

//Reference Types

objectstring

intx;

Console.WriteLine(x.GetType())

Console.WriteLine(typeof(int))

//Type conversion

floatd =3.5;

inti =(int) d

Constants

VB.NET

ConstMAX_AUTHORS AsInteger=25

ReadOnlyMIN_RANK AsSingle=5.00

C#

constintMAX_AUTHORS =25;

readonlyfloatMIN_RANKING =5.00;


3/16

Enumerations

VB.NET

EnumActionStart

'Stop is a reserved word[Stop]

RewindForward

EndEnum

EnumStatusFlunk =50

Pass =70

Excel =90EndEnum

Dima AsAction =Action.StopIfa Action.Start Then_'Prints "Stop is 1"

System.Console.WriteLine(a.ToString & " is "

& a)

'Prints 70System.Console.WriteLine(Status.Pass)

'Prints Pass

System.Console.WriteLine(Status.Pass.ToString())

EnumWeekdaysSaturdaySunday

Monday

TuesdayWednesdayThursday

Friday

EndEnum'Weekdays

C#

enumAction {Start, Stop, Rewind,Forward};

enumStatus {Flunk =50, Pass =70, Excel=90};

Action a =Action.Stop;if(a !=Action.Start)

//Prints "Stop is 1"

System.Console.WriteLine(a +" is "+(int) a);

// Prints 70

System.Console.WriteLine((int)Status.Pass);// Prints Pass

System.Console.WriteLine(Status.Pass);

enumWeekdays

{Saturday, Sunday, Monday, Tuesday,

Wednesday, Thursday, Friday

}


4/16

Operators

VB.NET

'Comparison= < > =

'Arithmetic

+ - * /

Mod\ (integerdivision)^ (raisetoa power)

'Assignment

= += -= *= /= \= ^= = &=

'BitwiseAnd AndAlso Or OrElse Not >

'Logical

And AndAlso Or OrElse Not

'String Concatenation&

C#

//Comparison == < > = !=

//Arithmetic

+ - * /

% (mod)/ (integer division ifboth operands areints)

Math.Pow(x, y)

//Assignment

= += -= *= /= %= &= |= ^= = ++ --

//Bitwise

& | ^ ~ >

//Logical&& || !

//String Concatenation

+


5/16

Choices

VB.NET

greeting =IIf(age < 20, "What's up?", "Hello")

'One line doesn't require "End If", no "Else"

Iflanguage ="VB.NET"ThenlangType ="verbose"

'Use: to put two commands on same line

Ifx 100 Andy < 5 Thenx *= 5 : y *= 2

'Preferred

Ifx 100 Andy < 5 Then

x *= 5y *= 2

EndIf

'or to break up any long single command use _IfhenYouHaveAReally < longLine And_itNeedsToBeBrokenInto2 > Lines Then_

UseTheUnderscore(charToBreakItUp)

Ifx > 5 Thenx *= y

ElseIfx =5 Thenx += y

ElseIfx < 10 Then

x -= y

Else

x /= yEndIf

'Must be a primitive data type

SelectCasecolorCase"black", "red"r += 1

Case"blue"

b += 1

Case"green"g += 1

CaseElse

other += 1

EndSelect

C#

greeting =age < 20 ? "What's up?":

"Hello";

if(x !=100 && y < 5){

// Multiple statements must be enclosedin {}

x *= 5;y *= 2;

}

if(x > 5)x *= y;

elseif(x == 5)x += y;

elseif(x < 10)

x -= y;else

x /= y;

//Must be integer or stringswitch(color){

case"black":

case"red": r++;break;case"blue"

break;

case"green": g++;break;default: other++;

break;

}


6/16

Loops

VB.NET

'Pre-test Loops:Whilec < 10

c += 1EndWhileDoUntilc =10

c += 1

Loop

'Post-test Loop:

DoWhilec < 10

c += 1Loop

Forc =2 To10 Step2

System.Console.WriteLine(c)Next

'Array or collection looping

Dimnames AsString() ={"Steven", "SuOk","Sarah"}ForEachs AsStringInnames

System.Console.WriteLine(s)

Next

C#

//Pre-test Loops: while (i < 10)i++;

for(i =2; i < =10; i += 2)System.Console.WriteLine(i);

//Post-test Loop:do

i++;

while(i < 10);

// Array or collection loopingstring[] names ={"Steven", "SuOk","Sarah"};

foreach(strings innames)

System.Console.WriteLine(s);

Arrays

VB.NET

Dimnums() AsInteger={1, 2, 3}Fori AsInteger=0 Tonums.Length -1

Console.WriteLine(nums(i))Next

C#

int[] nums ={1, 2, 3};for(inti =0; i < nums.Length; i++)

Console.WriteLine(nums[i]);


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'4 is the index of the last element, so it holds5 elementsDimnames(4) AsString

names(0) ="Steven"

'Throws System.IndexOutOfRangeException

names(5) ="Sarah"

'Resize the array, keeping the existing'values (Preserve is optional)ReDimPreservenames(6)

DimtwoD(rows-1, cols-1) AsSingletwoD(2, 0) =4.5

Dimjagged()() AsInteger={ _NewInteger(4) {}, NewInteger(1) {}, New

Integer(2) {} }

jagged(0)(4) =5

// 5 is the size of the array

string[] names =newstring[5];names[0] ="Steven";

// Throws System.IndexOutOfRangeException

names[5] ="Sarah"

// C# can't dynamically resize an array.

//Just copy into new array.string[] names2 =newstring[7];// or names.CopyTo(names2, 0);

Array.Copy(names, names2, names.Length);

float[,] twoD =newfloat[rows, cols];

twoD[2,0] =4.5;

int[][] jagged =newint[3][] {

newint[5], newint[2], newint[3] };jagged[0][4] =5;

Functions

VB.NET

'Pass by value (in, default), reference'(in/out), and reference (out)SubTestFunc(ByValx AsInteger, ByRefy AsInteger,

ByRefz AsInteger)x += 1y += 1

z =5

EndSub

'c set to zero by default

Dima =1, b =1, c AsInteger

TestFunc(a, b, c)

System.Console.WriteLine("{0} {1} {2}", a, b, c)'1 2 5

C#

// Pass by value (in, default), reference//(in/out), and reference (out)voidTestFunc(intx, refinty, outintz) {

x++;y++;z =5;

}

inta =1, b =1, c; // c doesn't needinitializing

TestFunc(a, refb, outc);

System.Console.WriteLine("{0} {1} {2}",a, b, c); // 1 2 5


8/16

'Accept variable number of arguments

FunctionSum(ByValParamArraynums AsInteger())AsInteger

Sum =0

ForEachi AsIntegerInnums

Sum += i

Next

EndFunction'Or use a Return statement like C#

Dimtotal AsInteger=Sum(4, 3, 2, 1) 'returns10

'Optional parameters must be listed last

'and must have a default valueSubSayHello(ByValname AsString,

OptionalByValprefix AsString="")

System.Console.WriteLine("Greetings, "&prefix& " "& name)

EndSub

SayHello("Steven", "Dr.")

SayHello("SuOk")

// Accept variable number of arguments

intSum(paramsint[] nums) {

intsum =0;foreach(inti innums)

sum += i;

returnsum;

}

inttotal =Sum(4, 3, 2, 1); // returns10

/* C# doesn't support optionalarguments/parameters.Just create two different versions of thesame function. */

voidSayHello(stringname, stringprefix){

System.Console.WriteLine("Greetings, "+prefix +" "+name);

}

voidSayHello(stringname) {

SayHello(name, "");

}

Exception Handling

VB.NET

ClassWithfinallyPublicSharedSubMain()

TryDimx AsInteger=5Dimy AsInteger=0

Dimz AsInteger=x /y

Console.WriteLine(z)

Catche AsDivideByZeroException

System.Console.WriteLine("Erroroccurred")

FinallySystem.Console.WriteLine("Thank you")

EndTry

EndSub'MainEndClass'Withfinally

C#

class Withfinally{

publicstaticvoidMain(){try

{

intx =5;

inty =0;

intz =x/y;

Console.WriteLine(z);

}catch(DivideByZeroException e)

{

System.Console.WriteLine("Erroroccurred");

}

finally


9/16

{

System.Console.WriteLine("Thankyou");

}

}

}

Namespaces

VB.NET

NamespaceASPAlliance.DotNet.Community

...

EndNamespace

'or

NamespaceASPAllianceNamespaceDotNet

NamespaceCommunity

...EndNamespace

EndNamespace

EndNamespace

ImportsASPAlliance.DotNet.Community

C#

namespaceASPAlliance.DotNet.Community {

...

}

// or

namespaceASPAlliance {

namespaceDotNet {

namespaceCommunity {

...}

}

}

usingASPAlliance.DotNet.Community;

Classes / Interfaces

VB.NET

'Accessibility keywordsPublicPrivate

Friend

ProtectedProtectedFriend

Shared

'Inheritance

ClassArticles

InheritsAuthors...

EndClass

ImportsSystem

C#

//Accessibility keywordspublicprivate

internal

protectedprotectedinternal

static

//Inheritance

classArticles: Authors {

...}

usingSystem;


10/16

InterfaceIArticleSubShow()

EndInterface'IArticle

_

ClassIAuthor

ImplementsIArticle

PublicSubShow()

System.Console.WriteLine("Show() methodImplemented")

EndSub'Show

'Entry point which delegates to C-style mainPrivate Function

PublicOverloadsSharedSubMain()

Main(System.Environment.GetCommandLineArgs())

EndSub

OverloadsPublicSharedSubMain(args() AsString)

Dimauthor AsNewIAuthor()

author.Show()

EndSub'Main

EndClass'IAuthor

interfaceIArticle

{voidShow();

}

classIAuthor:IArticle

{

publicvoidShow(){System.Console.WriteLine("Show()

method Implemented");

}

publicstaticvoidMain(string[] args)

{IAuthor author =newIAuthor();author.Show();

}

}

Constructors / Destructors

VB.NET

ClassTopAuthorPrivate_topAuthor AsInteger

PublicSubNew()_topAuthor =0

EndSub

PublicSubNew(ByValtopAuthor AsInteger)

Me._topAuthor =topAuthor

EndSub

ProtectedOverridesSubFinalize()

'Desctructor code to free unmanaged resources

MyBase.Finalize()EndSub

EndClass

C#

classTopAuthor {privateint_topAuthor;

publicTopAuthor() {_topAuthor =0;

}

publicTopAuthor(inttopAuthor) {

this._topAuthor= topAuthor

}

~TopAuthor() {

// Destructor code to free unmanagedresources.

// Implicitly creates a Finalizemethod

}


11/16

}

Objects

VB.NET

Dimauthor AsTopAuthor =NewTopAuthor

Withauthor

.Name ="Steven"

.AuthorRanking =3EndWith

author.Rank("Scott")

author.Demote() 'Calling Shared method

'orTopAuthor.Rank()

Dimauthor2 AsTopAuthor =author 'Both refer tosame object

author2.Name ="Joe"

System.Console.WriteLine(author2.Name) 'Prints

Joe

author =Nothing'Free the object

Ifauthor IsNothingThen_author =NewTopAuthor

Dimobj AsObject=NewTopAuthor

IfTypeOfobj IsTopAuthor Then_System.Console.WriteLine("Is a TopAuthor

object.")

C#

TopAuthor author =newTopAuthor();

//No "With" construct

author.Name ="Steven";author.AuthorRanking =3;

author.Rank("Scott");

TopAuthor.Demote() //Calling staticmethod

TopAuthor author2 =author //Both referto same object

author2.Name ="Joe";System.Console.WriteLine(author2.Name)

//Prints Joe

author =null//Free the object

if(author == null)author =newTopAuthor();

Object obj =newTopAuthor();if(obj isTopAuthor)

SystConsole.WriteLine("Is a TopAuthorobject.");

Structs

VB.NET

StructureAuthorRecordPublicname AsString

Publicrank AsSingle

PublicSubNew(ByValname AsString, ByVal

rank AsSingle)Me.name =name

Me.rank =rankEndSub

EndStructure

Dimauthor AsAuthorRecord =NewAuthorRecord("Steven", 8.8)Dimauthor2 AsAuthorRecord =author

C#

structAuthorRecord {publicstringname;

publicfloatrank;

publicAuthorRecord(stringname, float

rank) {

this.name =name;

this.rank =rank;}

}

AuthorRecord author =newAuthorRecord("Steven", 8.8);AuthorRecord author2 =author


12/16

author2.name ="Scott"

System.Console.WriteLine(author.name) 'PrintsStevenSystem.Console.WriteLine(author2.name) 'PrintsScott

author.name ="Scott";

SystemConsole.WriteLine(author.name);//Prints Steven

System.Console.WriteLine(author2.name);//Prints Scott

Properties

VB.NET

Private_size AsInteger

PublicPropertySize() AsIntegerGet

Return_size

EndGet

Set(ByValValue AsInteger)

IfValue < 0 Then

_size =0

Else_size =Value

EndIf

EndSetEndProperty

C#

privateint_size;

publicintSize {get {

return_size;

}

set {

if(value < 0)

_size =0;

else_size =value;

}

}


13/16

foo.Size += 1

ImportsSystem

Class[Date]

PublicPropertyDay() AsInteger

GetReturnday

EndGet

Set

day=value

EndSetEndProperty

PrivatedayAsInteger

PublicPropertyMonth() AsInteger

Get

ReturnmonthEndGet

Set

month=value

EndSetEndProperty

PrivatemonthAsInteger

PublicPropertyYear() AsInteger

Get

ReturnyearEndGetSet

year=value

EndSetEndPropertyPrivateyearAsInteger

PublicFunctionIsLeapYear(yearAsInteger)AsBoolean

Return(IfyearMod4 =0 ThenTrueElseFalse)

EndFunction'IsLeapYear

PublicSubSetDate(dayAsInteger, monthAsInteger,yearAsInteger)

Me.day=day

Me.month=monthMe.year=year

EndSub'SetDate

EndClass'[Date]

foo.Size++;

usingSystem;

classDate

{

publicintDay{

get {

returnday;

}set {

day =value;

}

}

intday;

publicintMonth{get {

returnmonth;

}

set {month =value;

}

}

intmonth;

publicintYear{

get {returnyear;

}

set {year =value;

}

}

intyear;

publicboolIsLeapYear(intyear)

{

returnyear%4== 0 ? true: false;

}

publicvoidSetDate (intday, intmonth, intyear)

{

this.day =day;

this.month =month;this.year =year;

}

}

Delegates / Events

VB.NET

DelegateSubMsgArrivedEventHandler(ByValmessage

AsString)

C#

delegatevoidMsgArrivedEventHandler(stringmessage);


14/16

EventMsgArrivedEvent AsMsgArrivedEventHandler

'or to define an event which declares a

'delegate implicitly

EventMsgArrivedEvent(ByValmessage AsString)

AddHandlerMsgArrivedEvent, AddressOfMy_MsgArrivedCallback'Won't throw an exception if obj is Nothing

RaiseEventMsgArrivedEvent("Test message")

RemoveHandlerMsgArrivedEvent, AddressOfMy_MsgArrivedCallback

ImportsSystem.Windows.Forms

'WithEvents can't be used on local variableDimWithEventsMyButton AsButton

MyButton =NewButton

PrivateSubMyButton_Click(ByValsender AsSystem.Object, _

ByVale AsSystem.EventArgs) HandlesMyButton.Click

MessageBox.Show(Me, "Button was clicked","Info", _

MessageBoxButtons.OK,MessageBoxIcon.Information)EndSub

eventMsgArrivedEventHandlerMsgArrivedEvent;

//Delegates must be used with events inC#

MsgArrivedEvent += newMsgArrivedEventHandler

(My_MsgArrivedEventCallback);//Throws exception if obj is null

MsgArrivedEvent("Test message");

MsgArrivedEvent -= newMsgArrivedEventHandler

(My_MsgArrivedEventCallback);

usingSystem.Windows.Forms;

Button MyButton =newButton();

MyButton.Click += newSystem.EventHandler(MyButton_Click);

privatevoidMyButton_Click(objectsender, System.EventArgs e) {

MessageBox.Show(this, "Button wasclicked", "Info",

MessageBoxButtons.OK,MessageBoxIcon.Information);}

Console I/O

VB.NET

'Special character constantsvbCrLf, vbCr, vbLf, vbNewLinevbNullString

vbTab

vbBack

vbFormFeed

vbVerticalTab

""

Chr(65) 'Returns 'A'

System.Console.Write("What's your name? ")Dimname AsString=System.Console.ReadLine()System.Console.Write("How old are you? ")

Dimage AsInteger=

C#

//Escape sequences\n, \r\t

\\

\

Convert.ToChar(65) //Returns 'A' -equivalent to Chr(num) in VB// or

(char) 65

System.Console.Write("What's your name?");


15/16

Val(System.Console.ReadLine())

System.Console.WriteLine("{0} is {1} yearsold.", name, age)'or

System.Console.WriteLine(name & " is "& age & "years old.")

Dimc AsInteger

c =System.Console.Read() 'Read single char

System.Console.WriteLine(c) 'Prints 65 if userenters "A"

stringname =SYstem.Console.ReadLine();

System.Console.Write("How old are you?");intage =Convert.ToInt32(System.Console.ReadLine());

System.Console.WriteLine("{0} is {1}

years old.", name, age);

//or

System.Console.WriteLine(name +" is "+age +" years old.");

intc =System.Console.Read(); //Readsingle charSystem.Console.WriteLine(c); //Prints 65if user enters "A"

File I/O

VB.NET

ImportsSystem.IO

'Write out to text file

Dimwriter AsStreamWriter =File.CreateText

("c:\myfile.txt")writer.WriteLine("Out to file.")

writer.Close()

'Read all lines from text file

Dimreader AsStreamReader =File.OpenText

C#

usingSystem.IO;

//Write out to text file

StreamWriter writer =File.CreateText

("c:\\myfile.txt");writer.WriteLine("Out to file.");

writer.Close();

//Read all lines from text file

StreamReader reader =File.OpenText


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Documents

Vb and c# Comaprison