Effective C#50 Specific Way to Improve Your C#

Item 50

Effective C#50 Specific Way to Improve Your C#

Item 50

Scott68.Chang

AgendaAgenda

• Item 50: Learn About the ECMA Standard

Item 50: Learn About the ECMA Standard

European Computer Manufacturers Association (ECMA)European Computer Manufacturers Association (ECMA)• The ECMA standard is the official word on how

every feature in the C# language behaves. – ECMA-334 defines the 1.0 standard for the C# language.– ECMA-335 defines the Common Language Runtime (CLR)

and Common Language Infrastructure (CLI) standards.

Goals of C#Goals of C#

• C# is intended to be a simple, modern, general-purpose, object-oriented programming language.

• The language should provide:– strong type checking, array bounds checking, detection of

attempts to use uninitialized variables, and automatic garbage collection

– Software robustness, durability, and programmer productivity are important.

• The language is intended for use in developing software components suitable for deployment in distributed environments.

Goals of C# (cont.)Goals of C# (cont.)

• Source code portability is very important– especially for those programmers already familiar with C

and C++.• Support for internationalization is very important.• C# is intended to be suitable for

– writing applications for both hosted and embedded systems,

– ranging from the very large that use sophisticated operating systems, down to the very small having dedicated functions.

Goals of C# (cont.)Goals of C# (cont.)

• C# applications are intended to be economical with regard to memory and processing power requirements– the language was not intended to compete directly on

performance and size with C or assembly language.

ECMA 334ECMA 334

• The representation of C# programs;• The syntax and constraints of the C# language;• The semantic rules for interpreting C# programs;• The restrictions and limits imposed by a

conforming implementation of C#.• The mechanism by which C# programs are

transformed for use by a data-processing system;• The mechanism by which C# applications are

invoked for use by a data-processing system;

ECMA 334 (cont.)ECMA 334 (cont.)

• The mechanism by which input data are transformed for use by a C# application;

• The mechanism by which output data are transformed after being produced by a C# application;

• The size or complexity of a program and its data that will exceed the capacity of any specific data processing system or the capacity of a particular processor;

• All minimal requirements of a data-processing system that is capable of supporting a conforming implementation.

Common Language Infrastructure (CLI)Common Language Infrastructure (CLI)

• Written in multiple high-level languages can be executed in different system environments without the need to rewrite those applications to take into consideration the unique characteristics of those environments.

ECMA 335ECMA 335

• Concepts and Architecture – Overall architecture of the CLI– Common Type System (CTS)– Virtual Execution System (VES)– Common Language Specification (CLS)

• Metadata Definition and Semantics– physical layout (as a file format)– logical contents (as a set of tables and their relationships)– semantics (as seen from a hypothetical assembler, ilasm)

• CIL Instruction Set– Describes the Common Intermediate Language (CIL)

instruction set.

ECMA 335 (cont.)ECMA 335 (cont.)

• Profiles and Libraries– Overview of the CLI Libraries, – A companion file, CLILibrary.xml, provides details of each

class, value type, and interface in the CLI Libraries.• Debug Interchange Format

– Describes a standard way to interchange debugging information between CLI producers and consumers.

• Annexes– Sample programs written in CIL Assembly Language

(ILAsm)– machine-readable description of the CIL instruction set – a set of guidelines used in the design of the libraries and

portability considerations.

SummarySummary

• ECMA 334 可參考– The C# Programming Language, by Anders Hejlsberg, Scott

Wiltamuth, and Peter Golde (Addison-Wesley, 2003). • ECMA 335 可參考

– The Common Language Infrastructure Annotated Standard, by James Miller and Susann Ragsdale (Addison-Wesley, 2003).