C# 语言规范_版本5.0 (第20章 附录B_语法)

A. 语法

此附录是主文档中描述的词法和语法以及不安全代码的语法扩展的摘要。这里，各语法产生式是按它们在主文档中出现的顺序列出的。

A.1 词法文法

input:
input-section_opt

input-section:
input-section-part
input-section   input-section-part

input-section-part:
input-elements_opt   new-line
pp-directive

input-elements:
input-element
input-elements   input-element

input-element:
whitespace
comment
token

A.1.1 行结束符

new-line:
Carriage return character (U+000D)
Line feed character (U+000A)
Carriage return character (U+000D) followed by line feed character (U+000A)
Next line character (U+0085)
Line separator character (U+2028)
Paragraph separator character (U+2029)

A.1.2 注释

comment:
single-line-comment
delimited-comment

single-line-comment:
//   input-characters_opt

input-characters:
input-character
input-characters   input-character

input-character:
Any Unicode character except a new-line-character

new-line-character:
Carriage return character (U+000D)
Line feed character (U+000A)
Next line character (U+0085)
Line separator character (U+2028)
Paragraph separator character (U+2029)

delimited-comment:
/*   delimited-comment-text_opt   asterisks   /

delimited-comment-text:
delimited-comment-section
delimited-comment-text   delimited-comment-section

delimited-comment-section:
/
asterisks_opt   not-slash-or-asterisk

asterisks:
*
asterisks   *

not-slash-or-asterisk:
Any Unicode character except / or *

A.1.3 空白

whitespace:
Any character with Unicode class Zs
Horizontal tab character (U+0009)
Vertical tab character (U+000B)
Form feed character (U+000C)

A.1.4 标记

token:
identifier
keyword
integer-literal
real-literal
character-literal
string-literal
operator-or-punctuator

A.1.5 Unicode 字符转义序列

unicode-escape-sequence:
\u   hex-digit   hex-digit   hex-digit   hex-digit
\U   hex-digit   hex-digit   hex-digit  hex-digit   hex-digit   hex-digit   hex-digit   hex-digit

A.1.6 标识符

identifier:
available-identifier
@   identifier-or-keyword

available-identifier:
An identifier-or-keyword that is not a keyword

identifier-or-keyword:
identifier-start-character   identifier-part-characters_opt

identifier-start-character:
letter-character
_ (the underscore character U+005F)

identifier-part-characters:
identifier-part-character
identifier-part-characters   identifier-part-character

identifier-part-character:
letter-character
decimal-digit-character
connecting-character
combining-character
formatting-character

letter-character:
A Unicode character of classes Lu, Ll, Lt, Lm, Lo, or Nl
A unicode-escape-sequence representing a character of classes Lu, Ll, Lt, Lm, Lo, or Nl

combining-character:
A Unicode character of classes Mn or Mc
A unicode-escape-sequence representing a character of classes Mn or Mc

decimal-digit-character:
A Unicode character of the class Nd
A unicode-escape-sequence representing a character of the class Nd

connecting-character: 
A Unicode character of the class Pc
A unicode-escape-sequence representing a character of the class Pc

formatting-character: 
A Unicode character of the class Cf
A unicode-escape-sequence representing a character of the class Cf

A.1.7 关键字

keyword:  one of
abstract    as            base          bool          break
byte        case          catch         char          checked
class           const         continue      decimal       default
delegate    do            double     else          enum
event           explicit      extern     false         finally
fixed           float         for        foreach       goto
if              implicit      in            int        interface
internal    is            lock          long          namespace
new         null          object     operator      out
override    params     private       protected  public
readonly    ref        return     sbyte         sealed
short           sizeof     stackalloc static     string
struct      switch     this          throw         true
try         typeof     uint          ulong         unchecked
unsafe      ushort     using         virtual       void
volatile    while

A.1.8 文本

literal:
boolean-literal
integer-literal
real-literal
character-literal
string-literal
null-literal

boolean-literal:
true
false

integer-literal:
decimal-integer-literal
hexadecimal-integer-literal

decimal-integer-literal:
decimal-digits   integer-type-suffix_opt

decimal-digits:
decimal-digit
decimal-digits   decimal-digit

decimal-digit:  one of
0  1  2  3  4  5  6  7  8  9

integer-type-suffix:  one of
U  u  L  l  UL  Ul  uL  ul  LU  Lu  lU  lu

hexadecimal-integer-literal:
0x   hex-digits   integer-type-suffix_opt
0X   hex-digits   integer-type-suffix_opt

hex-digits:
hex-digit
hex-digits   hex-digit

hex-digit:  one of
0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F  a  b  c  d  e  f

real-literal:
decimal-digits   .   decimal-digits   exponent-part_opt   real-type-suffix_opt
.   decimal-digits   exponent-part_opt   real-type-suffix_opt
decimal-digits   exponent-part   real-type-suffix_opt
decimal-digits   real-type-suffix

exponent-part:
e   sign_opt   decimal-digits
E   sign_opt   decimal-digits

sign:  one of
+  -

real-type-suffix:  one of
F  f  D  d  M  m

character-literal:
'   character   '

character:
single-character
simple-escape-sequence
hexadecimal-escape-sequence
unicode-escape-sequence

single-character:
 Any character except ' (U+0027), \ (U+005C), and new-line-character

simple-escape-sequence:  one of
\'  \"  \\  \0  \a  \b  \f  \n  \r  \t  \v

hexadecimal-escape-sequence:
\x   hex-digit   hex-digit_opt   hex-digit_opt   hex-digit_opt

string-literal:
regular-string-literal
verbatim-string-literal

regular-string-literal:
"   regular-string-literal-characters_opt   "

regular-string-literal-characters:
regular-string-literal-character
regular-string-literal-characters   regular-string-literal-character

regular-string-literal-character:
single-regular-string-literal-character
simple-escape-sequence
hexadecimal-escape-sequence
unicode-escape-sequence

single-regular-string-literal-character:
Any character except " (U+0022), \ (U+005C), and new-line-character

verbatim-string-literal:
@"   verbatim-string-literal-characters_opt   "

verbatim-string-literal-characters:
verbatim-string-literal-character
verbatim-string-literal-characters   verbatim-string-literal-character

verbatim-string-literal-character:
single-verbatim-string-literal-character
quote-escape-sequence

single-verbatim-string-literal-character:
any character except "

quote-escape-sequence:
""

null-literal:
null

A.1.9 运算符和标点符号

operator-or-punctuator:  one of
{    }      [      ]      (      )      .      ,      :      ;
+    -      *      /      %      &      |      ^      !      ~
=    <      >      ?      ??     ::     ++     --     &&     ||
->       ==     !=     <=     >=     +=     -=     *=     /=     %=
&=       |=     ^=     <<     <<= =>

right-shift:
>|>

right-shift-assignment:
>|>=

A.1.10 预处理指令

pp-directive:
pp-declaration
pp-conditional
pp-line
pp-diagnostic
pp-region
pp-pragma

conditional-symbol:
Any identifier-or-keyword except true or false

pp-expression:
whitespace_opt   pp-or-expression   whitespace_opt

pp-or-expression:
pp-and-expression
pp-or-expression   whitespace_opt   ||   whitespace_opt   pp-and-expression

pp-and-expression:
pp-equality-expression
pp-and-expression   whitespace_opt   &&   whitespace_opt   pp-equality-expression

pp-equality-expression:
pp-unary-expression
pp-equality-expression   whitespace_opt   ==   whitespace_opt   pp-unary-expression
pp-equality-expression   whitespace_opt   !=   whitespace_opt   pp-unary-expression

pp-unary-expression:
pp-primary-expression
!   whitespace_opt   pp-unary-expression

pp-primary-expression:
true
false
conditional-symbol
(   whitespace_opt   pp-expression   whitespace_opt   )

pp-declaration:
whitespace_opt   #   whitespace_opt   define   whitespace   conditional-symbol   pp-new-line
whitespace_opt   #   whitespace_opt   undef   whitespace   conditional-symbol   pp-new-line

pp-new-line:
whitespace_opt   single-line-comment_opt   new-line

pp-conditional:
pp-if-section   pp-elif-sections_opt   pp-else-section_opt   pp-endif

pp-if-section:
whitespace_opt   #   whitespace_opt   if   whitespace   pp-expression   pp-new-line   conditional-section_opt

pp-elif-sections:
pp-elif-section
pp-elif-sections   pp-elif-section

pp-elif-section:
whitespace_opt   #   whitespace_opt   elif   whitespace   pp-expression   pp-new-line   conditional-section_opt

pp-else-section:
whitespace_opt   #   whitespace_opt   else   pp-new-line   conditional-section_opt

pp-endif:
whitespace_opt   #   whitespace_opt   endif   pp-new-line

conditional-section:
input-section
skipped-section

skipped-section:
skipped-section-part
skipped-section   skipped-section-part

skipped-section-part:
skipped-characters_opt   new-line
pp-directive

skipped-characters:
whitespace_opt   not-number-sign   input-characters_opt

not-number-sign:
Any input-character except #

pp-diagnostic:
whitespace_opt   #   whitespace_opt   error   pp-message
whitespace_opt   #   whitespace_opt   warning   pp-message

pp-message:
new-line
whitespace   input-characters_opt   new-line

pp-region:
pp-start-region   conditional-section_opt   pp-end-region

pp-start-region:
whitespace_opt   #   whitespace_opt   region   pp-message

pp-end-region:
whitespace_opt   #   whitespace_opt   endregion   pp-message

pp-line:
whitespace_opt   #   whitespace_opt   line   whitespace   line-indicator   pp-new-line

line-indicator:
decimal-digits   whitespace   file-name
decimal-digits
default
hidden

file-name:
"   file-name-characters   "

file-name-characters:
file-name-character
file-name-characters   file-name-character

file-name-character:
Any input-character except "

pp-pragma:
whitespace_opt   #   whitespace_opt   pragma   whitespace   pragma-body   pp-new-line

pragma-body:
pragma-warning-body

pragma-warning-body:
warning   whitespace   warning-action
warning   whitespace   warning-action   whitespace   warning-list

warning-action:
disable
restore

warning-list:
decimal-digits
warning-list   whitespace_opt   ,   whitespace_opt   decimal-digits

A.2 句法文法

A.2.1 基本概念

namespace-name:
namespace-or-type-name

type-name:
namespace-or-type-name

namespace-or-type-name:
identifier   type-argument-list_opt
namespace-or-type-name   .   identifier   type-argument-list_opt
qualified-alias-member

A.2.2 类型

type:
value-type
reference-type
type-parameter

value-type:
struct-type
enum-type

struct-type:
type-name
simple-type
nullable-type

simple-type:
numeric-type
bool

numeric-type:
integral-type
floating-point-type
decimal

integral-type:
sbyte
byte
short
ushort
int
uint
long
ulong
char

floating-point-type:
float
double

nullable-type:
non-nullable-value-type   ?

non-nullable-value-type:
type

enum-type:
type-name

reference-type:
class-type
interface-type
array-type
delegate-type

class-type:
type-name
object
dynamic
string

interface-type:
type-name

rank-specifiers:
rank-specifier
rank-specifiers   rank-specifier

rank-specifier:
[   dim-separators_opt   ]

 dim-separators:
,
dim-separators   ,

delegate-type:
type-name

type-argument-list:
<   type-arguments   >

type-arguments:
type-argument
type-arguments   ,   type-argument

type-argument:
type

type-parameter:
identifier

A.2.3 变量

variable-reference:
expression

A.2.4 表达式

argument-list:
argument
argument-list   ,   argument

argument:
argument-name_opt   argument-value

argument-name:
identifier   :

argument-value:
expression
ref   variable-reference
out   variable-reference

primary-expression:
primary-no-array-creation-expression
array-creation-expression

primary-no-array-creation-expression:
literal
simple-name
parenthesized-expression
member-access
invocation-expression
element-access
this-access
base-access
post-increment-expression
post-decrement-expression
object-creation-expression
delegate-creation-expression
anonymous-object-creation-expression
typeof-expression
 checked-expression
unchecked-expression
default-value-expression
anonymous-method-expression

simple-name:
identifier   type-argument-list_opt

parenthesized-expression:
(   expression   )

member-access:
primary-expression   .   identifier  type-argument-list_opt
predefined-type   .   identifier  type-argument-list_opt
qualified-alias-member   .   identifier

predefined-type:  one of
bool     byte       char       decimal    double float      int    long
object   sbyte      short      string uint       ulong      ushort

invocation-expression:
primary-expression   (   argument-list_opt   )

element-access:
primary-no-array-creation-expression   [   argument-list   ]

this-access:
this

base-access:
base   .   identifier
base   [   argument-list   ]

post-increment-expression:
primary-expression   ++

post-decrement-expression:
primary-expression   --

object-creation-expression:
new   type   (   argument-list_opt   )   object-or-collection-initializer_opt
new   type   object-or-collection-initializer

object-or-collection-initializer:
object-initializer
collection-initializer

object-initializer:
{   member-initializer-list_opt   }
{   member-initializer-list   ,   }

member-initializer-list:
member-initializer
member-initializer-list   ,   member-initializer

member-initializer:
identifier   =   initializer-value

initializer-value:
expression
object-or-collection-initializer

collection-initializer:
{   element-initializer-list   }
{   element-initializer-list   ,   }

element-initializer-list:
element-initializer
element-initializer-list   ,   element-initializer

element-initializer:
non-assignment-expression
{   expression-list   }

expression-list:
expression
expression-list   ,   expression

array-creation-expression:
new   non-array-type   [   expression-list   ]   rank-specifiers_opt   array-initializer_opt
new   array-type   array-initializer
new   rank-specifier   array-initializer

delegate-creation-expression:
new   delegate-type   (   expression   )

anonymous-object-creation-expression:
new   anonymous-object-initializer

anonymous-object-initializer:
{   member-declarator-list_opt   }
{   member-declarator-list   ,   }

member-declarator-list:
member-declarator
member-declarator-list   ,   member-declarator

member-declarator:
simple-name
member-access
identifier   =   expression

typeof-expression:
typeof   (   type   )
typeof   (   unbound-type-name   )
typeof ( void )

unbound-type-name:
identifier   generic-dimension-specifier_opt
identifier   ::   identifier   generic-dimension-specifier_opt
unbound-type-name   .   identifier   generic-dimension-specifier_opt

generic-dimension-specifier:
<   commas_opt   >

commas:
,
commas   ,

checked-expression:
checked   (   expression   )

unchecked-expression:
unchecked   (   expression   )

default-value-expression:
default   (   type   )

unary-expression:
primary-expression
+   unary-expression
-   unary-expression
!   unary-expression
~   unary-expression
pre-increment-expression
pre-decrement-expression
cast-expression

pre-increment-expression:
++   unary-expression

pre-decrement-expression:
--   unary-expression

cast-expression:
(   type   )   unary-expression

multiplicative-expression:
unary-expression
multiplicative-expression   *   unary-expression
multiplicative-expression   /   unary-expression
multiplicative-expression   %   unary-expression

additive-expression:
multiplicative-expression
additive-expression   +   multiplicative-expression
additive-expression   –   multiplicative-expression

shift-expression:
additive-expression
shift-expression   <<   additive-expression
shift-expression   right-shift   additive-expression

relational-expression:
shift-expression
relational-expression   <   shift-expression
relational-expression   >   shift-expression
relational-expression   <=   shift-expression
relational-expression   >=   shift-expression
relational-expression   is   type
relational-expression   as   type

equality-expression:
relational-expression
equality-expression   ==   relational-expression
equality-expression   !=   relational-expression

and-expression:
equality-expression
and-expression   &   equality-expression

exclusive-or-expression:
and-expression
exclusive-or-expression   ^   and-expression

inclusive-or-expression:
exclusive-or-expression
inclusive-or-expression   |   exclusive-or-expression

conditional-and-expression:
inclusive-or-expression
conditional-and-expression   &&   inclusive-or-expression

conditional-or-expression:
conditional-and-expression
conditional-or-expression   ||   conditional-and-expression

null-coalescing-expression:
conditional-or-expression
conditional-or-expression   ??   null-coalescing-expression

conditional-expression:
null-coalescing-expression
null-coalescing-expression   ?   expression   :   expression

lambda-expression:
anonymous-function-signature   =>   anonymous-function-body

anonymous-method-expression:
delegate   explicit-anonymous-function-signature_opt   block

anonymous-function-signature:
explicit-anonymous-function-signature
implicit-anonymous-function-signature

explicit-anonymous-function-signature:
(   explicit-anonymous-function-parameter-list_opt   )

explicit-anonymous-function-parameter-list:
explicit-anonymous-function-parameter
explicit-anonymous-function-parameter-list   ,   explicit-anonymous-function-parameter

explicit-anonymous-function-parameter:
anonymous-function-parameter-modifier_opt   type   identifier

anonymous-function-parameter-modifier:
ref
out

implicit-anonymous-function-signature:
(   implicit-anonymous-function-parameter-list_opt   )
implicit-anonymous-function-parameter

implicit-anonymous-function-parameter-list:
implicit-anonymous-function-parameter
implicit-anonymous-function-parameter-list   ,   implicit-anonymous-function-parameter

implicit-anonymous-function-parameter:
identifier

anonymous-function-body:
expression
block

query-expression:
from-clause   query-body

from-clause:
from   type_opt   identifier   in   expression

query-body:
query-body-clauses_opt   select-or-group-clause   query-continuation_opt

query-body-clauses:
query-body-clause
query-body-clauses   query-body-clause

query-body-clause:
from-clause
let-clause
where-clause
join-clause
join-into-clause
orderby-clause

let-clause:
let   identifier   =   expression

where-clause:
where   boolean-expression

join-clause:
join   type_opt   identifier   in   expression   on   expression   equals   expression

join-into-clause:
join   type_opt   identifier   in   expression   on   expression   equals   expression   into   identifier

orderby-clause:
orderby   orderings

orderings:
ordering
orderings   ,   ordering

ordering:
expression    ordering-direction_opt

ordering-direction:
ascending
descending

select-or-group-clause:
select-clause
group-clause

select-clause:
select   expression

group-clause:
group   expression   by   expression

query-continuation:
into   identifier   query-body

assignment:
unary-expression   assignment-operator   expression

assignment-operator:
=
+=
-=
*=
/=
%=
&=
|=
^=
<<=
right-shift-assignment

expression:
non-assignment-expression
assignment

non-assignment-expression:
conditional-expression
lambda-expression
query-expression

constant-expression:
expression

boolean-expression:
expression

A.2.5 语句

statement:
labeled-statement
declaration-statement
embedded-statement

embedded-statement:
block
empty-statement
expression-statement
selection-statement
iteration-statement
jump-statement
try-statement
checked-statement
unchecked-statement
lock-statement
using-statement
yield-statement

block:
{   statement-list_opt   }

statement-list:
statement
statement-list   statement

empty-statement:
;

labeled-statement:
identifier   :   statement

declaration-statement:
local-variable-declaration   ;
local-constant-declaration   ;

local-variable-declaration:
local-variable-type   local-variable-declarators

local-variable-type:
type
var

local-variable-declarators:
local-variable-declarator
local-variable-declarators   ,   local-variable-declarator

local-variable-declarator:
identifier
identifier   =   local-variable-initializer

local-variable-initializer:
expression
array-initializer

local-constant-declaration:
const   type   constant-declarators

constant-declarators:
constant-declarator
constant-declarators   ,   constant-declarator

constant-declarator:
identifier   =   constant-expression

expression-statement:
statement-expression   ;

statement-expression:
invocation-expression
object-creation-expression
assignment
post-increment-expression
post-decrement-expression
pre-increment-expression
pre-decrement-expression

selection-statement:
if-statement
switch-statement

if-statement:
if   (   boolean-expression   )   embedded-statement
if   (   boolean-expression   )   embedded-statement   else   embedded-statement

switch-statement:
switch   (   expression   )   switch-block

switch-block:
{   switch-sections_opt   }

switch-sections:
switch-section
switch-sections   switch-section

switch-section:
switch-labels   statement-list

switch-labels:
switch-label
switch-labels   switch-label

switch-label:
case   constant-expression   :
default   :

iteration-statement:
while-statement
do-statement
for-statement
foreach-statement

while-statement:
while   (   boolean-expression   )   embedded-statement

do-statement:
do   embedded-statement   while   (   boolean-expression   )   ;

for-statement:
for   (   for-initializer_opt   ;   for-condition_opt   ;   for-iterator_opt   )   embedded-statement

for-initializer:
local-variable-declaration
statement-expression-list

for-condition:
boolean-expression

for-iterator:
statement-expression-list

statement-expression-list:
statement-expression
statement-expression-list   ,   statement-expression

foreach-statement:
foreach   (   local-variable-type   identifier   in   expression   )   embedded-statement

jump-statement:
break-statement
continue-statement
goto-statement
return-statement
throw-statement

break-statement:
break   ;

continue-statement:
continue   ;

goto-statement:
goto   identifier   ;
goto   case   constant-expression   ;
goto   default   ;

return-statement:
return   expression_opt   ;

throw-statement:
throw   expression_opt   ;

try-statement:
try   block   catch-clauses
try   block   finally-clause
try   block   catch-clauses   finally-clause

catch-clauses:
specific-catch-clauses   general-catch-clause_opt
specific-catch-clauses_opt   general-catch-clause

specific-catch-clauses:
specific-catch-clause
specific-catch-clauses   specific-catch-clause

specific-catch-clause:
catch   (   class-type   identifier_opt   )   block

general-catch-clause:
catch   block

finally-clause:
finally   block

checked-statement:
checked   block

unchecked-statement:
unchecked   block

lock-statement:
lock   (   expression   )   embedded-statement

using-statement:
using   (    resource-acquisition   )    embedded-statement

resource-acquisition:
local-variable-declaration
expression

yield-statement:
yield   return   expression   ;
yield   break   ;

A.2.6 命名空间

compilation-unit:
extern-alias-directives_opt   using-directives_opt  global-attributes_opt
          namespace-member-declarations_opt

namespace-declaration:
namespace   qualified-identifier   namespace-body   ;_opt

qualified-identifier:
identifier
qualified-identifier   .   identifier

namespace-body:
{   extern-alias-directives_opt   using-directives_opt   namespace-member-declarations_opt   }

extern-alias-directives:
extern-alias-directive
extern-alias-directives   extern-alias-directive

extern-alias-directive:
extern   alias   identifier   ;

using-directives:
using-directive
using-directives   using-directive

using-directive:
using-alias-directive
using-namespace-directive

using-alias-directive:
using   identifier   =   namespace-or-type-name   ;

using-namespace-directive:
using   namespace-name   ;

namespace-member-declarations:
namespace-member-declaration
namespace-member-declarations   namespace-member-declaration

namespace-member-declaration:
namespace-declaration
type-declaration

type-declaration:
class-declaration
struct-declaration
interface-declaration
enum-declaration
delegate-declaration

qualified-alias-member:
identifier   ::   identifier   type-argument-list_opt

A.2.7 类

class-declaration:
attributes_opt   class-modifiers_opt   partial_opt   class   identifier   type-parameter-list_opt
          class-base_opt   type-parameter-constraints-clauses_opt   class-body   ;_opt

class-modifiers:
class-modifier
class-modifiers   class-modifier

class-modifier:
new
public
protected
internal
private
abstract
sealed
static

type-parameter-list:
<   type-parameters   >

type-parameters:
attributes_opt   type-parameter
type-parameters   ,   attributes_opt   type-parameter

type-parameter:
identifier

class-base:
:   class-type
:   interface-type-list
:   class-type   ,   interface-type-list

interface-type-list:
interface-type
interface-type-list   ,   interface-type

type-parameter-constraints-clauses:
type-parameter-constraints-clause
type-parameter-constraints-clauses   type-parameter-constraints-clause

type-parameter-constraints-clause:
where   type-parameter   :   type-parameter-constraints

type-parameter-constraints:
primary-constraint
secondary-constraints
constructor-constraint
primary-constraint   ,   secondary-constraints
primary-constraint   ,   constructor-constraint
secondary-constraints   ,   constructor-constraint
primary-constraint   ,   secondary-constraints   ,   constructor-constraint

primary-constraint:
class-type
class
struct

secondary-constraints:
interface-type
type-parameter
secondary-constraints   ,   interface-type
secondary-constraints   ,   type-parameter

constructor-constraint:
new   (   )

class-body:
{   class-member-declarations_opt   }

class-member-declarations:
class-member-declaration
class-member-declarations   class-member-declaration

class-member-declaration:
constant-declaration
field-declaration
method-declaration
property-declaration
event-declaration
indexer-declaration
operator-declaration
constructor-declaration
destructor-declaration
static-constructor-declaration
type-declaration

constant-declaration:
attributes_opt   constant-modifiers_opt   const   type   constant-declarators   ;

constant-modifiers:
constant-modifier
constant-modifiers   constant-modifier

constant-modifier:
new
public
protected
internal
private

constant-declarators:
constant-declarator
constant-declarators   ,   constant-declarator

constant-declarator:
identifier   =   constant-expression

field-declaration:
attributes_opt   field-modifiers_opt   type   variable-declarators   ;

field-modifiers:
field-modifier
field-modifiers   field-modifier

field-modifier:
new
public
protected
internal
private
static
readonly
volatile

variable-declarators:
variable-declarator
variable-declarators   ,   variable-declarator

variable-declarator:
identifier
identifier   =   variable-initializer

variable-initializer:
expression
array-initializer

method-declaration:
method-header   method-body

method-header:
attributes_opt   method-modifiers_opt   partial_opt   return-type   member-name   type-parameter-list_opt
          (   formal-parameter-list_opt   )   type-parameter-constraints-clauses_opt

method-modifiers:
method-modifier
method-modifiers   method-modifier

method-modifier:
new
public
protected
internal
private
static
virtual
sealed
override
abstract
extern

return-type:
type
void

member-name:
identifier
interface-type   .   identifier

method-body:
block
;

formal-parameter-list:
fixed-parameters
fixed-parameters   ,   parameter-array
parameter-array

fixed-parameters:
fixed-parameter
fixed-parameters   ,   fixed-parameter

fixed-parameter:
attributes_opt   parameter-modifier_opt   type   identifier   default-argument_opt

default-argument:
=  expression

parameter-modifier:
ref
out
this

parameter-array:
attributes_opt   params   array-type   identifier

property-declaration:
attributes_opt   property-modifiers_opt   type   member-name   {   accessor-declarations   }

property-modifiers:
property-modifier
property-modifiers   property-modifier

property-modifier:
new
public
protected
internal
private
static
virtual
sealed
override
abstract
extern

member-name:
identifier
interface-type   .   identifier

accessor-declarations:
get-accessor-declaration   set-accessor-declaration_opt
set-accessor-declaration   get-accessor-declaration_opt

get-accessor-declaration:
attributes_opt   accessor-modifier_opt    get   accessor-body

set-accessor-declaration:
attributes_opt   accessor-modifier_opt   set   accessor-body

accessor-modifier:
protected
internal
private
protected   internal
internal   protected

accessor-body:
block
;

event-declaration:
attributes_opt   event-modifiers_opt   event   type   variable-declarators   ;
attributes_opt   event-modifiers_opt   event   type   member-name   {   event-accessor-declarations   }

event-modifiers:
event-modifier
event-modifiers   event-modifier

event-modifier:
new
public
protected
internal
private
static
virtual
sealed
override
abstract
extern

event-accessor-declarations:
add-accessor-declaration   remove-accessor-declaration
remove-accessor-declaration   add-accessor-declaration

add-accessor-declaration:
attributes_opt   add   block

remove-accessor-declaration:
attributes_opt   remove   block

indexer-declaration:
attributes_opt   indexer-modifiers_opt   indexer-declarator   {   accessor-declarations   }

indexer-modifiers:
indexer-modifier
indexer-modifiers   indexer-modifier

indexer-modifier:
new
public
protected
internal
private
virtual
sealed
override
abstract
extern

indexer-declarator:
type   this   [   formal-parameter-list   ]
type   interface-type   .   this   [   formal-parameter-list   ]

operator-declaration:
attributes_opt   operator-modifiers   operator-declarator   operator-body

operator-modifiers:
operator-modifier
operator-modifiers   operator-modifier

operator-modifier:
public
static
extern

operator-declarator:
unary-operator-declarator
binary-operator-declarator
conversion-operator-declarator

unary-operator-declarator:
type   operator   overloadable-unary-operator   (   type   identifier   )

overloadable-unary-operator:  one of
+   -   !   ~   ++   --   true   false

binary-operator-declarator:
type   operator   overloadable-binary-operator   (   type   identifier   ,   type   identifier   )

overloadable-binary-operator:
+
-
*
/
%
&
|
^
<<
right-shift
==
!=
>
<
>=
<=

conversion-operator-declarator:
implicit   operator   type   (   type   identifier   )
explicit   operator   type   (   type   identifier   )

operator-body:
block
;

constructor-declaration:
attributes_opt   constructor-modifiers_opt   constructor-declarator   constructor-body

constructor-modifiers:
constructor-modifier
constructor-modifiers   constructor-modifier

constructor-modifier:
public
protected
internal
private
extern

constructor-declarator:
identifier   (   formal-parameter-list_opt   )   constructor-initializer_opt

constructor-initializer:
:   base   (   argument-list_opt   )
:   this   (   argument-list_opt   )

constructor-body:
block
;

static-constructor-declaration:
attributes_opt   static-constructor-modifiers  identifier   (   )   static-constructor-body

static-constructor-modifiers:
extern_opt static
static extern_opt

static-constructor-body:
block
;

destructor-declaration:
attributes_opt   extern_opt   ~   identifier   (   )    destructor-body

destructor-body:
block
;

A.2.8 结构

struct-declaration:
attributes_opt   struct-modifiers_opt   partial_opt   struct   identifier   type-parameter-list_opt
          struct-interfaces_opt   type-parameter-constraints-clauses_opt   struct-body   ;_opt

struct-modifiers:
struct-modifier
struct-modifiers   struct-modifier

struct-modifier:
new
public
protected
internal
private

struct-interfaces:
:   interface-type-list

struct-body:
{   struct-member-declarations_opt   }

struct-member-declarations:
struct-member-declaration
struct-member-declarations   struct-member-declaration

struct-member-declaration:
constant-declaration
field-declaration
method-declaration
property-declaration
event-declaration
indexer-declaration
operator-declaration
constructor-declaration
static-constructor-declaration
type-declaration

A.2.9 数组

array-type:
non-array-type   rank-specifiers

non-array-type:
type

rank-specifiers:
rank-specifier
rank-specifiers   rank-specifier

rank-specifier:
[   dim-separators_opt   ]

dim-separators:
,
dim-separators   ,

array-initializer:
{   variable-initializer-list_opt   }
{   variable-initializer-list   ,   }

variable-initializer-list:
variable-initializer
variable-initializer-list   ,   variable-initializer

variable-initializer:
expression
array-initializer

A.2.10 接口

interface-declaration:
attributes_opt   interface-modifiers_opt   partial_opt   interface  
          identifier   variant-type-parameter-list_opt   interface-base_opt
          type-parameter-constraints-clauses_opt   interface-body   ;_opt

interface-modifiers:
interface-modifier
interface-modifiers   interface-modifier

interface-modifier:
new
public
protected
internal
private

variant-type-parameter-list:
<   variant-type-parameters   >

variant-type-parameters:
attributes_opt  variance-annotation_opt  type-parameter
variant-type-parameters   ,   attributes_opt   variance-annotation_opt  type-parameter

variance-annotation:
in
out

interface-base:
:   interface-type-list

interface-body:
{   interface-member-declarations_opt   }

interface-member-declarations:
interface-member-declaration
interface-member-declarations   interface-member-declaration

interface-member-declaration:
interface-method-declaration
interface-property-declaration
interface-event-declaration
interface-indexer-declaration

interface-method-declaration:
attributes_opt   new_opt   return-type   identifier   type-parameter-list
          (   formal-parameter-list_opt   )   type-parameter-constraints-clauses_opt   ;

interface-property-declaration:
attributes_opt   new_opt   type   identifier   {   interface-accessors   }

interface-accessors:
attributes_opt   get   ;
attributes_opt   set   ;
attributes_opt   get   ;   attributes_opt   set   ;
attributes_opt   set   ;   attributes_opt   get   ;

interface-event-declaration:
attributes_opt   new_opt   event   type   identifier   ;

interface-indexer-declaration:
attributes_opt   new_opt   type   this   [   formal-parameter-list   ]   {   interface-accessors   }

A.2.11 枚举

enum-declaration:
attributes_opt   enum-modifiers_opt   enum   identifier   enum-base_opt   enum-body   ;_opt

enum-base:
:   integral-type

enum-body:
{   enum-member-declarations_opt   }
{   enum-member-declarations   ,   }

enum-modifiers:
enum-modifier
enum-modifiers   enum-modifier

enum-modifier:
new
public
protected
internal
private

enum-member-declarations:
enum-member-declaration
enum-member-declarations   ,   enum-member-declaration

enum-member-declaration:
attributes_opt   identifier
attributes_opt   identifier   =   constant-expression

A.2.12 委托

delegate-declaration:
attributes_opt   delegate-modifiers_opt   delegate   return-type  
          identifier  variant-type-parameter-list_opt  
          (   formal-parameter-list_opt   )   type-parameter-constraints-clauses_opt   ;

delegate-modifiers:
delegate-modifier
delegate-modifiers   delegate-modifier

delegate-modifier:
new
public
protected
internal
private

A.2.13 特性

global-attributes:
global-attribute-sections

global-attribute-sections:
global-attribute-section
global-attribute-sections   global-attribute-section

global-attribute-section:
[   global-attribute-target-specifier   attribute-list   ]
[   global-attribute-target-specifier   attribute-list   ,   ]

global-attribute-target-specifier:
global-attribute-target   :

global-attribute-target:
assembly
module

attributes:
attribute-sections

attribute-sections:
attribute-section
attribute-sections   attribute-section

attribute-section:
[   attribute-target-specifier_opt   attribute-list   ]
[   attribute-target-specifier_opt   attribute-list   ,   ]

attribute-target-specifier:
attribute-target   :

attribute-target:
field
event
method
param
property
return
type

attribute-list:
attribute
attribute-list   ,   attribute

attribute:
attribute-name   attribute-arguments_opt

attribute-name:
 type-name

attribute-arguments:
(   positional-argument-list_opt   )
(   positional-argument-list   ,   named-argument-list   )
(   named-argument-list   )

positional-argument-list:
positional-argument
positional-argument-list   ,   positional-argument

positional-argument:
argument-name_opt   attribute-argument-expression

named-argument-list:
named-argument
named-argument-list   ,   named-argument

named-argument:
identifier   =   attribute-argument-expression

attribute-argument-expression:
expression

A.3 不安全代码的语法扩展

class-modifier:
...
unsafe

struct-modifier:
...
unsafe

interface-modifier:
...
unsafe

delegate-modifier:
...
unsafe

field-modifier:
...
unsafe

method-modifier:
...
unsafe

property-modifier:
...
unsafe

event-modifier:
...
unsafe

indexer-modifier:
...
unsafe

operator-modifier:
...
unsafe

constructor-modifier:
...
unsafe

destructor-declaration:
attributes_opt   extern_opt   unsafe_opt   ~   identifier   (   )    destructor-body
attributes_opt   unsafe_opt   extern_opt   ~   identifier   (   )    destructor-body

static-constructor-modifiers:
extern_opt   unsafe_opt   static
unsafe_opt   extern_opt   static
extern_opt   static   unsafe_opt
unsafe_opt   static   extern_opt
static   extern_opt   unsafe_opt
static   unsafe_opt   extern_opt

embedded-statement:
...
unsafe-statement
fixed-statement

unsafe-statement:
unsafe   block

type:
...
pointer-type

pointer-type:
unmanaged-type   *
void   *

unmanaged-type:
type

primary-no-array-creation-expression:
...
pointer-member-access
pointer-element-access
sizeof-expression

unary-expression:
...
pointer-indirection-expression
addressof-expression

pointer-indirection-expression:
*   unary-expression

pointer-member-access:
primary-expression   ->   identifier  type-argument-list_opt

pointer-element-access:
primary-no-array-creation-expression   [   expression   ]

addressof-expression:
&   unary-expression

sizeof-expression:
sizeof   (   unmanaged-type   )

fixed-statement:
fixed   (   pointer-type   fixed-pointer-declarators   )   embedded-statement

fixed-pointer-declarators:
fixed-pointer-declarator
fixed-pointer-declarators   ,   fixed-pointer-declarator

fixed-pointer-declarator:
identifier   =   fixed-pointer-initializer

fixed-pointer-initializer:
&   variable-reference
expression

struct-member-declaration:
…
fixed-size-buffer-declaration

fixed-size-buffer-declaration:
attributes_opt   fixed-size-buffer-modifiers_opt   fixed   buffer-element-type
          fixed-size-buffer-declarators   ;

fixed-size-buffer-modifiers:
fixed-size-buffer-modifier
fixed-size-buffer-modifier   fixed-size-buffer-modifiers

fixed-size-buffer-modifier:
new
public
protected
internal
private
unsafe

buffer-element-type:
type

fixed-size-buffer-declarators:
fixed-size-buffer-declarator
fixed-size-buffer-declarator   fixed-size-buffer-declarators

fixed-size-buffer-declarator:
identifier   [   constant-expression   ]

local-variable-initializer:
…
stackalloc-initializer

stackalloc-initializer:
stackalloc   unmanaged-type   [   expression   ]