Identifiers and Keywords

 
Chapter 2 - C# Basics
bySimon Robinsonet al.
Wrox Press 2002
  

In this final section of this basics of C# chapter, we examine the rules governing what names we can use for variables , classes, methods , and so on.

Identifiers are the names we give to variables, to user -defined types such as classes and structs, and to members of these types. Identifiers are case sensitive, so identifier and Identifier would be different variables. There are a couple of rules determining what identifiers we can use in C#:

  • They must begin with a letter or underscore , although they can contain numeric characters

  • We can't use C# keywords as identifiers

C# has the following reserved keywords:

abstract

do

implicit

params

switch

as

double

in

private

this

base

else

int

protected

throw

bool

enum

interface

public

true

break

event

internal

readonly

try

byte

explicit

is

ref

typeof

case

extern

lock

return

uint

catch

false

long

sbyte

ulong

char

finally

namespace

sealed

unchecked

checked

fixed

new

short

unsafe

class

float

null

sizeof

ushort

const

for

object

stackalloc

using

continue

foreach

operator

static

virtual

decimal

goto

out

string

volatile

default

if

override

struct

void

delegate

     

while

If we do need to use one of these words as an identifier (for example, if we are accessing a class written in a different language), we can prefix the identifier with the @ symbol to indicate to the compiler that what follows is to be treated as an identifier, not as a C# keyword (so abstract is not a valid identifier, but @abstract is).

Finally, identifiers can also contain Unicode characters, specified using the syntax \uXXXX , where XXXX is the four-digit hex code for the Unicode character. The following are some examples of valid identifiers:

  • Name



Professional C#. 2nd Edition
Performance Consulting: A Practical Guide for HR and Learning Professionals
ISBN: 1576754359
EAN: 2147483647
Year: 2002
Pages: 244

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