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VB.NET and C# Comparison
This is a quick reference guide to highlight some key syntactical differences between VB.NETand C#. Hope you find this useful!
Thank you to Tom Shelton, Fergus Cooney, and others for your input.
Comments
Data Types
Constants
Enumerations
Operators
Choices
Loops
Arrays
Functions
Exception Handling
Namespaces
Classes / Interfaces
Constructors / Destructors
Objects
Structs
Properties
Delegates / Events
Console I/O
File I/O
VB.NET
C#
Comments
'''' Single line only
Rem Single line only
// Single line
/* Multiple
line */
/// XML comments on single line
/** XML comments on multiple lines */
Data Types
Value Types
Boolean
Byte
Char (example: "A"c)
Short, Integer, Long
Single, Double
Decimal
Date
Reference Types
Object
String
Dim x As Integer
Console.WriteLine(x.GetType()) '''' Prints System.Int32
Console.WriteLine(TypeName(x)) '''' Prints Integer
'''' Type conversion
Dim numDecimal As Single = 3.5
Dim numInt As Integer
numInt = CType(numDecimal, Integer) '''' set to 4 (Banker''''s rounding)
numInt = CInt(numDecimal) '''' same result as CType
numInt = Int(numDecimal) '''' set to 3 (Int function truncates the decimal)
Value Types
bool
byte, sbyte
char (example: ''''A'''')
short, ushort, int, uint, long, ulong
float, double
decimal
DateTime (not a built-in C# type)
Reference Types
object
string
int x;
Console.WriteLine(x.GetType()); // Prints System.Int32
Console.WriteLine(typeof(int)); // Prints System.Int32
// Type conversion
double numDecimal = 3.5;
int numInt = (int) numDecimal; // set to 3 (truncates decimal)
Constants
Const MAX_STUDENTS As Integer = 25
const int MAX_STUDENTS = 25;
Enumerations
Enum Action
Start
[Stop] '''' Stop is a reserved word
Rewind
Forward
End Enum
Enum Status
Flunk = 50
Pass = 70
Excel = 90
End Enum
Dim a As Action = Action.Stop
If a <> Action.Start Then Console.WriteLine(a) '''' Prints 1
Console.WriteLine(Status.Pass) '''' Prints 70
Dim s As Type = GetType(Status)
Console.WriteLine([Enum].GetName(s, Status.Pass)) '''' Prints Pass
enum Action {Start, Stop, Rewind, Forward};
enum Status {Flunk = 50, Pass = 70, Excel = 90};
Action a = Action.Stop;
if (a != Action.Start)
Console.WriteLine(a + " is " + (int) a); // Prints "Stop is 1"
Console.WriteLine(Status.Pass); // Prints Pass
Operators
Comparison
= < > <= >= <>
Arithmetic
+ - * /
Mod
\ (integer division)
^ (raise to a power)
Assignment
= += -= *= /= \= ^= <<= >>= &=
Bitwise
And AndAlso Or OrElse Not << >>
Logical
And AndAlso Or OrElse Not
Note: AndAlso and OrElse are for short-circuiting logical evaluations
String Concatenation
&
Comparison
== < > <= >= !=
Arithmetic
+ - * /
% (mod)
/ (integer division if both operands are ints)
Math.Pow(x, y)
Assignment
= += -= *= /= %= &= |= ^= <<= >>= ++ --
Bitwise
& | ^ ~ << >>
Logical
&& || !
Note: && and || perform short-circuit logical evaluations
String Concatenation
+
Choices
greeting = IIf(age < 20, "What''''s up?", "Hello")
'''' One line doesn''''t require "End If", no "Else"
If language = "VB.NET" Then langType = "verbose"
'''' Use : to put two commands on same line
If x <> 100 Then x *= 5 : y *= 2
'''' or to break up any long single command use _
If whenYouHaveAReally < longLine And itNeedsToBeBrokenInto2 > Lines Then _
UseTheUnderscore(charToBreakItUp)
''''If x > 5 Then
x *= y
ElseIf x = 5 Then
x += y
ElseIf x < 10 Then
x -= y
Else
x /= y
End If
Select Case color '''' Must be a primitive data type
Case "pink", "red"
r += 1
Case "blue"
b += 1
Case "green"
g += 1
Case Else
other += 1
End Select
greeting = age < 20 ? "What''''s up?" : "Hello";
if (x != 100) { // Multiple statements must be enclosed in {}
x *= 5;
y *= 2;
}
No need for _ or : since ; is used to terminate each statement.
if (x > 5)
x *= y;
else if (x == 5)
x += y;
else if (x < 10)
x -= y;
else
x /= y;
switch (color) { // Must be integer or string
case "pink":
case "red": r++; break; // break is mandatory; no fall-through
case "blue": b++; break;
case "green": g++; break;
default: other++; break; // break necessary on default
}
Loops
Pre-test Loops:
While c < 10
c += 1
End While
Do Until c = 10
c += 1
Loop
Do While c < 10
c += 1
Loop
For c = 2 To 10 Step 2
Console.WriteLine(c)
Next
Post-test Loops:
Do
c += 1
Loop While c < 10
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