- •Foreword
- •Introduction
- •Scope
- •Conformance
- •Normative references
- •Definitions
- •Notational conventions
- •Acronyms and abbreviations
- •General description
- •Language overview
- •Getting started
- •Types
- •Predefined types
- •Conversions
- •Array types
- •Type system unification
- •Variables and parameters
- •Automatic memory management
- •Expressions
- •Statements
- •Classes
- •Constants
- •Fields
- •Methods
- •Properties
- •Events
- •Operators
- •Indexers
- •Instance constructors
- •Destructors
- •Static constructors
- •Inheritance
- •Static classes
- •Partial type declarations
- •Structs
- •Interfaces
- •Delegates
- •Enums
- •Namespaces and assemblies
- •Versioning
- •Extern Aliases
- •Attributes
- •Generics
- •Why generics?
- •Creating and consuming generics
- •Multiple type parameters
- •Constraints
- •Generic methods
- •Anonymous methods
- •Iterators
- •Lexical structure
- •Programs
- •Grammars
- •Lexical grammar
- •Syntactic grammar
- •Grammar ambiguities
- •Lexical analysis
- •Line terminators
- •Comments
- •White space
- •Tokens
- •Unicode escape sequences
- •Identifiers
- •Keywords
- •Literals
- •Boolean literals
- •Integer literals
- •Real literals
- •Character literals
- •String literals
- •The null literal
- •Operators and punctuators
- •Pre-processing directives
- •Conditional compilation symbols
- •Pre-processing expressions
- •Declaration directives
- •Conditional compilation directives
- •Diagnostic directives
- •Region control
- •Line directives
- •Pragma directives
- •Basic concepts
- •Application startup
- •Application termination
- •Declarations
- •Members
- •Namespace members
- •Struct members
- •Enumeration members
- •Class members
- •Interface members
- •Array members
- •Delegate members
- •Member access
- •Declared accessibility
- •Accessibility domains
- •Protected access for instance members
- •Accessibility constraints
- •Signatures and overloading
- •Scopes
- •Name hiding
- •Hiding through nesting
- •Hiding through inheritance
- •Namespace and type names
- •Unqualified name
- •Fully qualified names
- •Automatic memory management
- •Execution order
- •Types
- •Value types
- •The System.ValueType type
- •Default constructors
- •Struct types
- •Simple types
- •Integral types
- •Floating point types
- •The decimal type
- •The bool type
- •Enumeration types
- •Reference types
- •Class types
- •The object type
- •The string type
- •Interface types
- •Array types
- •Delegate types
- •Boxing and unboxing
- •Boxing conversions
- •Unboxing conversions
- •Variables
- •Variable categories
- •Static variables
- •Instance variables
- •Instance variables in classes
- •Instance variables in structs
- •Array elements
- •Value parameters
- •Reference parameters
- •Output parameters
- •Local variables
- •Default values
- •Definite assignment
- •Initially assigned variables
- •Initially unassigned variables
- •Precise rules for determining definite assignment
- •General rules for statements
- •Block statements, checked, and unchecked statements
- •Expression statements
- •Declaration statements
- •If statements
- •Switch statements
- •While statements
- •Do statements
- •For statements
- •Break, continue, and goto statements
- •Throw statements
- •Return statements
- •Try-catch statements
- •Try-finally statements
- •Try-catch-finally statements
- •Foreach statements
- •Using statements
- •Lock statements
- •General rules for simple expressions
- •General rules for expressions with embedded expressions
- •Invocation expressions and object creation expressions
- •Simple assignment expressions
- •&& expressions
- •|| expressions
- •! expressions
- •?: expressions
- •Anonymous method expressions
- •Yield statements
- •Variable references
- •Atomicity of variable references
- •Conversions
- •Implicit conversions
- •Identity conversion
- •Implicit numeric conversions
- •Implicit enumeration conversions
- •Implicit reference conversions
- •Boxing conversions
- •Implicit type parameter conversions
- •Implicit constant expression conversions
- •User-defined implicit conversions
- •Explicit conversions
- •Explicit numeric conversions
- •Explicit enumeration conversions
- •Explicit reference conversions
- •Unboxing conversions
- •User-defined explicit conversions
- •Standard conversions
- •Standard implicit conversions
- •Standard explicit conversions
- •User-defined conversions
- •Permitted user-defined conversions
- •Evaluation of user-defined conversions
- •User-defined implicit conversions
- •User-defined explicit conversions
- •Anonymous method conversions
- •Method group conversions
- •Expressions
- •Expression classifications
- •Values of expressions
- •Operators
- •Operator precedence and associativity
- •Operator overloading
- •Unary operator overload resolution
- •Binary operator overload resolution
- •Candidate user-defined operators
- •Numeric promotions
- •Unary numeric promotions
- •Binary numeric promotions
- •Member lookup
- •Base types
- •Function members
- •Argument lists
- •Overload resolution
- •Applicable function member
- •Better function member
- •Better conversion
- •Function member invocation
- •Invocations on boxed instances
- •Primary expressions
- •Literals
- •Simple names
- •Invariant meaning in blocks
- •Parenthesized expressions
- •Member access
- •Identical simple names and type names
- •Invocation expressions
- •Method invocations
- •Delegate invocations
- •Element access
- •Array access
- •Indexer access
- •This access
- •Base access
- •Postfix increment and decrement operators
- •The new operator
- •Object creation expressions
- •Array creation expressions
- •Delegate creation expressions
- •The typeof operator
- •The checked and unchecked operators
- •Default value expression
- •Anonymous methods
- •Anonymous method signatures
- •Anonymous method blocks
- •Outer variables
- •Captured outer variables
- •Instantiation of local variables
- •Anonymous method evaluation
- •Implementation example
- •Unary expressions
- •Unary plus operator
- •Unary minus operator
- •Logical negation operator
- •Bitwise complement operator
- •Prefix increment and decrement operators
- •Cast expressions
- •Arithmetic operators
- •Multiplication operator
- •Division operator
- •Remainder operator
- •Addition operator
- •Subtraction operator
- •Shift operators
- •Relational and type-testing operators
- •Integer comparison operators
- •Floating-point comparison operators
- •Decimal comparison operators
- •Boolean equality operators
- •Enumeration comparison operators
- •Reference type equality operators
- •String equality operators
- •Delegate equality operators
- •The is operator
- •The as operator
- •Logical operators
- •Integer logical operators
- •Enumeration logical operators
- •Boolean logical operators
- •Conditional logical operators
- •Boolean conditional logical operators
- •User-defined conditional logical operators
- •Conditional operator
- •Assignment operators
- •Simple assignment
- •Compound assignment
- •Event assignment
- •Expression
- •Constant expressions
- •Boolean expressions
- •Statements
- •End points and reachability
- •Blocks
- •Statement lists
- •The empty statement
- •Labeled statements
- •Declaration statements
- •Local variable declarations
- •Local constant declarations
- •Expression statements
- •Selection statements
- •The if statement
- •The switch statement
- •Iteration statements
- •The while statement
- •The do statement
- •The for statement
- •The foreach statement
- •Jump statements
- •The break statement
- •The continue statement
- •The goto statement
- •The return statement
- •The throw statement
- •The try statement
- •The checked and unchecked statements
- •The lock statement
- •The using statement
- •The yield statement
- •Namespaces
- •Compilation units
- •Namespace declarations
- •Extern alias directives
- •Using directives
- •Using alias directives
- •Using namespace directives
- •Namespace members
- •Type declarations
- •Qualified alias member
- •Classes
- •Class declarations
- •Class modifiers
- •Abstract classes
- •Sealed classes
- •Static classes
- •Class base specification
- •Base classes
- •Interface implementations
- •Class body
- •Partial declarations
- •Class members
- •Inheritance
- •The new modifier
- •Access modifiers
- •Constituent types
- •Static and instance members
- •Nested types
- •Fully qualified name
- •Declared accessibility
- •Hiding
- •this access
- •Reserved member names
- •Member names reserved for properties
- •Member names reserved for events
- •Member names reserved for indexers
- •Member names reserved for destructors
- •Constants
- •Fields
- •Static and instance fields
- •Readonly fields
- •Using static readonly fields for constants
- •Versioning of constants and static readonly fields
- •Volatile fields
- •Field initialization
- •Variable initializers
- •Static field initialization
- •Instance field initialization
- •Methods
- •Method parameters
- •Value parameters
- •Reference parameters
- •Output parameters
- •Parameter arrays
- •Static and instance methods
- •Virtual methods
- •Override methods
- •Sealed methods
- •Abstract methods
- •External methods
- •Method body
- •Method overloading
- •Properties
- •Static and instance properties
- •Accessors
- •Virtual, sealed, override, and abstract accessors
- •Events
- •Field-like events
- •Event accessors
- •Static and instance events
- •Virtual, sealed, override, and abstract accessors
- •Indexers
- •Indexer overloading
- •Operators
- •Unary operators
- •Binary operators
- •Conversion operators
- •Instance constructors
- •Constructor initializers
- •Instance variable initializers
- •Constructor execution
- •Default constructors
- •Private constructors
- •Optional instance constructor parameters
- •Static constructors
- •Destructors
- •Structs
- •Struct declarations
- •Struct modifiers
- •Struct interfaces
- •Struct body
- •Struct members
- •Class and struct differences
- •Value semantics
- •Inheritance
- •Assignment
- •Default values
- •Boxing and unboxing
- •Meaning of this
- •Field initializers
- •Constructors
- •Destructors
- •Static constructors
- •Struct examples
- •Database integer type
- •Database boolean type
- •Arrays
- •Array types
- •The System.Array type
- •Array creation
- •Array element access
- •Array members
- •Array covariance
- •Arrays and the generic IList interface
- •Array initializers
- •Interfaces
- •Interface declarations
- •Interface modifiers
- •Base interfaces
- •Interface body
- •Interface members
- •Interface methods
- •Interface properties
- •Interface events
- •Interface indexers
- •Interface member access
- •Fully qualified interface member names
- •Interface implementations
- •Explicit interface member implementations
- •Interface mapping
- •Interface implementation inheritance
- •Interface re-implementation
- •Abstract classes and interfaces
- •Enums
- •Enum declarations
- •Enum modifiers
- •Enum members
- •The System.Enum type
- •Enum values and operations
- •Delegates
- •Delegate declarations
- •Delegate instantiation
- •Delegate invocation
- •Exceptions
- •Causes of exceptions
- •The System.Exception class
- •How exceptions are handled
- •Common Exception Classes
- •Attributes
- •Attribute classes
- •Attribute usage
- •Positional and named parameters
- •Attribute parameter types
- •Attribute specification
- •Attribute instances
- •Compilation of an attribute
- •Run-time retrieval of an attribute instance
- •Reserved attributes
- •The AttributeUsage attribute
- •The Conditional attribute
- •Conditional Methods
- •Conditional Attribute Classes
- •The Obsolete attribute
- •Unsafe code
- •Unsafe contexts
- •Pointer types
- •Fixed and moveable variables
- •Pointer conversions
- •Pointers in expressions
- •Pointer indirection
- •Pointer member access
- •Pointer element access
- •The address-of operator
- •Pointer increment and decrement
- •Pointer arithmetic
- •Pointer comparison
- •The sizeof operator
- •The fixed statement
- •Stack allocation
- •Dynamic memory allocation
- •Generics
- •Generic class declarations
- •Type parameters
- •The instance type
- •Members of generic classes
- •Static fields in generic classes
- •Static constructors in generic classes
- •Accessing protected members
- •Overloading in generic classes
- •Parameter array methods and type parameters
- •Overriding and generic classes
- •Operators in generic classes
- •Nested types in generic classes
- •Generic struct declarations
- •Generic interface declarations
- •Uniqueness of implemented interfaces
- •Explicit interface member implementations
- •Generic delegate declarations
- •Constructed types
- •Type arguments
- •Open and closed types
- •Base classes and interfaces of a constructed type
- •Members of a constructed type
- •Accessibility of a constructed type
- •Conversions
- •Using alias directives
- •Generic methods
- •Generic method signatures
- •Virtual generic methods
- •Calling generic methods
- •Inference of type arguments
- •Using a generic method with a delegate
- •Constraints
- •Satisfying constraints
- •Member lookup on type parameters
- •Type parameters and boxing
- •Conversions involving type parameters
- •Iterators
- •Iterator blocks
- •Enumerator interfaces
- •Enumerable interfaces
- •Yield type
- •This access
- •Enumerator objects
- •The MoveNext method
- •The Current property
- •The Dispose method
- •Enumerable objects
- •The GetEnumerator method
- •Implementation example
- •Lexical grammar
- •Line terminators
- •White space
- •Comments
- •Unicode character escape sequences
- •Identifiers
- •Keywords
- •Literals
- •Operators and punctuators
- •Pre-processing directives
- •Syntactic grammar
- •Basic concepts
- •Types
- •Expressions
- •Statements
- •Classes
- •Structs
- •Arrays
- •Interfaces
- •Enums
- •Delegates
- •Attributes
- •Generics
- •Grammar extensions for unsafe code
- •Undefined behavior
- •Implementation-defined behavior
- •Unspecified behavior
- •Other Issues
- •Capitalization styles
- •Pascal casing
- •Camel casing
- •All uppercase
- •Capitalization summary
- •Word choice
- •Namespaces
- •Classes
- •Interfaces
- •Enums
- •Static fields
- •Parameters
- •Methods
- •Properties
- •Events
- •Case sensitivity
- •Avoiding type name confusion
- •Documentation Comments
- •Introduction
- •Recommended tags
- •<code>
- •<example>
- •<exception>
- •<list>
- •<para>
- •<param>
- •<paramref>
- •<permission>
- •<remarks>
- •<returns>
- •<seealso>
- •<summary>
- •<value>
- •Processing the documentation file
- •ID string format
- •ID string examples
- •An example
- •C# source code
- •Resulting XML
Annex E Documentation Comments
1/// <value>
2/// The point's x-coordinate.
3/// </value>
4public int X
5{
6 |
get { return x; } |
7set { x = value; }
8}
9E.3 Processing the documentation file
10The following information is intended for C# implementations targeting the CLI.
11The documentation generator generates an ID string for each element in the source code that is tagged with a
12documentation comment. This ID string uniquely identifies a source element. A documentation viewer can
13use an ID string to identify the corresponding metadata/reflection item to which the documentation applies.
14The documentation file is not a hierarchical representation of the source code; rather, it is a flat list with a
15generated ID string for each element.
16E.3.1 ID string format
17The documentation generator observes the following rules when it generates the ID strings:
18• No white space is placed in the string.
19• The first part of the string identifies the kind of member being documented, via a single character
20followed by a colon. The following kinds of members are defined:
21
Character |
Description |
|
|
E |
Event |
|
|
F |
Field |
|
|
M |
Method (including constructors, destructors, and operators) |
|
|
N |
Namespace |
|
|
P |
Property (including indexers) |
|
|
T |
Type (such as class, delegate, enum, interface, and struct) |
|
|
! |
Error string; the rest of the string provides information about the |
|
error. For example, the documentation generator generates error |
|
information for links that cannot be resolved. |
|
|
22
23• The second part of the string is the fully qualified name of the element, starting at the root of the
24namespace. The name of the element, its enclosing type(s), and namespace are separated by periods. If
25the name of the item itself has periods, they are replaced by the NUMBER SIGN # (U+0023). (It is
26assumed that no element has this character in its name.)
27• For methods and properties with arguments, the argument list follows, enclosed in parentheses. For
28those without arguments, the parentheses are omitted. The arguments are separated by commas. The
29encoding of each argument is the same as a CLI signature, as follows: Arguments are represented by
30their fully qualified name. For example, int becomes System.Int32, string becomes
31System.String, object becomes System.Object, and so on. Arguments having the out or ref
32modifier have an @ following their type name. Arguments passed by value or via params have no
33special notation. Arguments that are arrays are represented as [ lowerbound : size , … , lowerbound :
34size ] where the number of commas is the rank less one, and the lower bounds and size of each
35dimension, if known, are represented in decimal. If a lower bound or size is not specified, it is omitted.
36If the lower bound and size for a particular dimension are omitted, the “:” is omitted as well. Jagged
37arrays are represented by one “[]” per level. Arguments that have pointer types other than void are
519
C# LANGUAGE SPECIFICATION
1represented using a * following the type name. A void pointer is represented using a type name of
2System.Void.
3E.3.2 ID string examples
4The following examples each show a fragment of C# code, along with the ID string produced from each
5source element capable of having a documentation comment:
6• Types are represented using their fully qualified name.
7enum Color { Red, Blue, Green }
8namespace Acme
9{
10 |
interface IProcess { … } |
11 |
struct ValueType { … } |
12 |
class Widget: IProcess |
13 |
{ |
14 |
public class NestedClass { … } |
15 |
public interface IMenuItem { … } |
16 |
public delegate void Del(int i); |
17 |
public enum Direction { North, South, East, West } |
18}
19}
20"T:Color"
21"T:Acme.IProcess"
22"T:Acme.ValueType"
23"T:Acme.Widget"
24"T:Acme.Widget.NestedClass"
25"T:Acme.Widget.IMenuItem"
26"T:Acme.Widget.Del"
27"T:Acme.Widget.Direction"
28• Fields are represented by their fully qualified name.
29namespace Acme
30{
31 |
struct ValueType |
32 |
{ |
33 |
private int total; |
34 |
} |
35 |
class Widget: IProcess |
36 |
{ |
37 |
public class NestedClass |
38 |
{ |
39 |
private int value; |
40 |
} |
41 |
private string message; |
42 |
private static Color defaultColor; |
43 |
private const double PI = 3.14159; |
44 |
protected readonly double monthlyAverage; |
45 |
private long[] array1; |
46 |
private Widget[,] array2; |
47 |
private unsafe int *pCount; |
48 |
private unsafe float **ppValues; |
49}
50}
520
Annex E Documentation Comments
1"F:Acme.ValueType.total"
2"F:Acme.Widget.NestedClass.value"
3"F:Acme.Widget.message"
4"F:Acme.Widget.defaultColor"
5"F:Acme.Widget.PI"
6"F:Acme.Widget.monthlyAverage"
7"F:Acme.Widget.array1"
8"F:Acme.Widget.array2"
9"F:Acme.Widget.pCount"
10"F:Acme.Widget.ppValues"
11• Constructors.
12namespace Acme
13{
14 |
class Widget: IProcess |
15 |
{ |
16 |
static Widget() { … } |
17 |
public Widget() { … } |
18 |
public Widget(string s) { … } |
19}
20}
21"M:Acme.Widget.#cctor"
22"M:Acme.Widget.#ctor"
23"M:Acme.Widget.#ctor(System.String)"
24• Destructors.
25namespace Acme
26{
27 |
class Widget: IProcess |
28 |
{ |
29 |
~Widget() { … } |
30}
31}
32"M:Acme.Widget.Finalize"
33• Methods.
34namespace Acme
35{
36 |
struct ValueType |
37 |
{ |
38 |
public void M(int i) { … } |
39 |
} |
40 |
class Widget: IProcess |
41 |
{ |
42 |
public class NestedClass |
43 |
{ |
44 |
public void M(int i) { … } |
45 |
} |
46 |
public static void M0() { … } |
47 |
public void M1(char c, out float f, ref ValueType v) { … } |
48 |
public void M2(short[] x1, int[,] x2, long[][] x3) { … } |
49 |
public void M3(long[][] x3, Widget[][,,] x4) { … } |
50 |
public unsafe void M4(char *pc, Color **pf) { … } |
51 |
public unsafe void M5(void *pv, double *[][,] pd) { … } |
52 |
public void M6(int i, params object[] args) { … } |
53}
54}
521
C# LANGUAGE SPECIFICATION
1"M:Acme.ValueType.M(System.Int32)"
2"M:Acme.Widget.NestedClass.M(System.Int32)"
3"M:Acme.Widget.M0"
4"M:Acme.Widget.M1(System.Char,System.Single@,Acme.ValueType@)"
5"M:Acme.Widget.M2(System.Int16[],System.Int32[0:,0:],System.Int64[][])"
6"M:Acme.Widget.M3(System.Int64[][],Acme.Widget[0:,0:,0:][])"
7"M:Acme.Widget.M4(System.Char*,Color**)"
8"M:Acme.Widget.M5(System.Void*,System.Double*[0:,0:][])"
9"M:Acme.Widget.M6(System.Int32,System.Object[])"
10• Properties and indexers.
11namespace Acme
12{
13 |
class Widget: IProcess |
14 |
{ |
15 |
public int Width {get { … } set { … }} |
16 |
public int this[int i] {get { … } set { … }} |
17 |
public int this[string s, int i] {get { … } set { … }} |
18}
19}
20"P:Acme.Widget.Width"
21"P:Acme.Widget.Item(System.Int32)"
22"P:Acme.Widget.Item(System.String,System.Int32)"
23• Events
24namespace Acme
25{
26 |
class Widget: IProcess |
27 |
{ |
28 |
public event Del AnEvent; |
29}
30}
31"E:Acme.Widget.AnEvent"
32• Unary operators.
33namespace Acme
34{
35 |
class Widget: IProcess |
36 |
{ |
37 |
public static Widget operator+(Widget x) { … } |
38}
39}
40"M:Acme.Widget.op_UnaryPlus(Acme.Widget)"
41The complete set of unary operator function names used is as follows: op_UnaryPlus,
42op_UnaryNegation, op_LogicalNot, op_OnesComplement, op_Increment,
43op_Decrement, op_True, and op_False.
44• Binary operators.
45namespace Acme
46{
47 |
class Widget: IProcess |
48 |
{ |
49 |
public static Widget operator+(Widget x1, Widget x2) { return x1; } |
50}
51}
52"M:Acme.Widget.op_Addition(Acme.Widget,Acme.Widget)"
53The complete set of binary operator function names used is as follows: op_Addition,
54op_Subtraction, op_Multiply, op_Division, op_Modulus, op_BitwiseAnd,
55op_BitwiseOr, op_ExclusiveOr, op_LeftShift, op_RightShift, op_Equality,
56op_Inequality, op_LessThan, op_LessThanOrEqual, op_GreaterThan, and
57op_GreaterThanOrEqual.
522