ISO/IEC 23270:2003

INTERNATIONAL ISO/IEC
STANDARD 23270
First edition
2003-04-01

Information technology — C# Language
Specification
Technologies de l'information — Spécification du langage C#


Reference number
ISO/IEC 23270:2003(E)
©
ISO/IEC 2003

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ISO/IEC 23270:2003(E)
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©  ISO/IEC 2003
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ISO/IEC 23270:2003(E)

Table of Contents
1. Scope. 1
2. Conformance . 3
3. References . 5
4. Definitions . 7
5. Notational conventions. 9
6. Acronyms and abbreviations . 11
7. General description. 13
8. Language Overview . 15
8.1 Getting started . 15
8.2 Types . 16
8.2.1 Predefined types.17
8.2.2 Conversions .19
8.2.3 Array types.20
8.2.4 Type system unification.21
8.3 Variables and parameters. 22
8.4 Automatic memory management. 25
8.5 Expressions. 27
8.6 Statements. 28
8.7 Classes . 31
8.7.1 Constants.32
8.7.2 Fields.33
8.7.3 Methods .34
8.7.4 Properties .35
8.7.5 Events.36
8.7.6 Operators.37
8.7.7 Indexers.38
8.7.8 Instance constructors.39
8.7.9 Destructors .39
8.7.10 Static constructors.40
8.7.11 Inheritance .40
8.8 Structs. 41
8.9 Interfaces . 42
8.10 Delegates . 43
8.11 Enums. 44
8.12 Namespaces and assemblies . 45
8.13 Versioning . 46
8.14 Attributes . 48
9. Lexical structure. 51
9.1 Programs. 51
9.2 Grammars . 51
9.2.1 Lexical grammar .51
9.2.2 Syntactic grammar .51
9.3 Lexical analysis . 52
9.3.1 Line terminators.52
9.3.2 Comments .53
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ISO/IEC 23270:2003(E)
9.3.3 White space.54
9.4 Tokens . 54
9.4.1 Unicode escape sequences .54
9.4.2 Identifiers.55
9.4.3 Keywords.56
9.4.4 Literals .57
9.4.5 Operators and punctuators .62
9.5 Pre-processing directives. 62
9.5.1 Conditional compilation symbols .63
9.5.2 Pre-processing expressions .63
9.5.3 Declaration directives .64
9.5.4 Conditional compilation directives .65
9.5.5 Diagnostic directives.67
9.5.6 Region control.67
9.5.7 Line directives.68
10. Basic concepts . 69
10.1 Application startup . 69
10.2 Application termination. 69
10.3 Declarations. 70
10.4 Members. 72
10.4.1 Namespace members .72
10.4.2 Struct members .72
10.4.3 Enumeration members .73
10.4.4 Class members .73
10.4.5 Interface members.73
10.4.6 Array members .73
10.4.7 Delegate members.73
10.5 Member access . 73
10.5.1 Declared accessibility .74
10.5.2 Accessibility domains .74
10.5.3 Protected access for instance members.77
10.5.4 Accessibility constraints .77
10.6 Signatures and overloading . 78
10.7 Scopes. 79
10.7.1 Name hiding.81
10.8 Namespace and type names. 83
10.8.1 Fully qualified names.84
10.9 Automatic memory management. 85
10.10 Execution order . 87
11. Types . 89
11.1 Value types . 89
11.1.1 Default constructors.90
11.1.2 Struct types .90
11.1.3 Simple types.91
11.1.4 Integral types.91
11.1.5 Floating point types.92
11.1.6 The decimal type.94
11.1.7 The bool type.94
11.1.8 Enumeration types .94
11.2 Reference types . 94
11.2.1 Class types .95
11.2.2 The object type.95
11.2.3 The string type.95
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ISO/IEC 23270:2003(E)
11.2.4 Interface types.96
11.2.5 Array types.96
11.2.6 Delegate types.96
11.3 Boxing and unboxing . 96
11.3.1 Boxing conversions.96
11.3.2 Unboxing conversions .97
12. Variables . 99
12.1 Variable categories . 99
12.1.1 Static variables.99
12.1.2 Instance variables.99
12.1.3 Array elements.100
12.1.4 Value parameters .100
12.1.5 Reference parameters.100
12.1.6 Output parameters.100
12.1.7 Local variables.101
12.2 Default values. 101
12.3 Definite assignment . 102
12.3.1 Initially assigned variables.102
12.3.2 Initially unassigned variables.103
12.3.3 Precise rules for determining definite assignment .103
12.4 Variable references. 112
12.5 Atomicity of variable references . 112
13. Conversions. 113
13.1 Implicit conversions . 113
13.1.1 Identity conversion .113
13.1.2 Implicit numeric conversions.113
13.1.3 Implicit enumeration conversions.114
13.1.4 Implicit reference conversions.114
13.1.5 Boxing conversions.114
13.1.6 Implicit constant expression conversions .114
13.1.7 User-defined implicit conversions .115
13.2 Explicit conversions . 115
13.2.1 Explicit numeric conversions.115
13.2.2 Explicit enumeration conversions.117
13.2.3 Explicit reference conversions.117
13.2.4 Unboxing conversions .117
13.2.5 User-defined explicit conversions.118
13.3 Standard conversions. 118
13.3.1 Standard implicit conversions.118
13.3.2 Standard explicit conversions .118
13.4 User-defined conversions . 118
13.4.1 Permitted user-defined conversions.118
13.4.2 Evaluation of user-defined conversions.119
13.4.3 User-defined implicit conversions .119
13.4.4 User-defined explicit conversions.120
14. Expressions . 123
14.1 Expression classifications. 123
14.1.1 Values of expressions .124
14.2 Operators . 124
14.2.1 Operator precedence and associativity.124
14.2.2 Operator overloading .125
14.2.3 Unary operator overload resolution .126
14.2.4 Binary operator overload resolution .127
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ISO/IEC 23270:2003(E)
14.2.5 Candidate user-defined operators .127
14.2.6 Numeric promotions .127
14.3 Member lookup . 129
14.3.1 Base types .129
14.4 Function members . 130
14.4.1 Argument lists.132
14.4.2 Overload resolution.134
14.4.3 Function member invocation .136
14.5 Primary expressions. 137
14.5.1 Literals .138
14.5.2 Simple names.138
14.5.3 Parenthesized expressions.139
14.5.4 Member access.140
14.5.5 Invocation expressions.141
14.5.6 Element access.143
14.5.7 This access .144
14.5.8 Base access .145
14.5.9 Postfix increment and decrement operators.145
14.5.10 The new operator.146
14.5.11 The typeof operator.150
14.5.12 The checked and unchecked operators .151
14.6 Unary expressions . 153
14.6.1 Unary plus operator.153
14.6.2 Unary minus operator .154
14.6.3 Logical negation operator .154
14.6.4 Bitwise complement operator .
...