Tutorial C#

The ECMA standard lists these design goals for C#:[5]

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

The language, and implementations thereof, should provide support for software engineering principles such as 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.

Source code portability is very important, as is programmer portability, 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.

Although 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.

Name[edit]

C-sharp musical note

The name "C sharp" was inspired by musical notation where a sharp indicates that the written note should be made a semitone higher in pitch.[6] This is similar to the language name of C++, where "++" indicates that a variable should be incremented by 1.

Due to technical limitations of display (standard fonts, browsers, etc.) and the fact that the sharp symbol (U+266F ♯ music sharp sign (HTML: ♯)) is not present on the standard keyboard, the number sign (U+0023 # number sign (HTML: #)) was chosen to represent the sharp symbol in the written name of the programming language.[7] This convention is reflected in the ECMA-334 C# Language Specification.[5] However, when it is practical to do so (for example, in advertising or in box art[8]), Microsoft uses the intended musical symbol.

The "sharp" suffix has been used by a number of other .NET languages that are variants of existing languages, including J# (a .NET language also designed by Microsoft that is derived from Java 1.1), A# (from Ada), and the functional programming language F#.[9] The original implementation of Eiffel for .NET was called Eiffel#,[10] a name retired since the full Eiffel language is now supported. The suffix has also been used for libraries, such as Gtk# (a .NET wrapper for GTK+ and other GNOME libraries), Cocoa# (a wrapper for Cocoa).

History[edit]

During the development of the .NET Framework, the class libraries were originally written using a managed code compiler system called Simple Managed C (SMC).[11][12][13] In January 1999, Anders Hejlsberg formed a team to build a new language at the time called Cool, which stood for "C-like Object Oriented Language".[14] Microsoft had considered keeping the name "Cool" as the final name of the language, but chose not to do so for trademark reasons. By the time the .NET project was publicly announced at the July 2000 Professional Developers Conference, the language had been renamed C#, and the class libraries and ASP.NET runtime had been ported to C#.

C#'s principal designer and lead architect at Microsoft is Anders Hejlsberg, who was previously involved with the design of Turbo Pascal, Embarcadero Delphi (formerly CodeGear Delphi, Inprise Delphi and Borland Delphi), and Visual J++. In interviews and technical papers he has stated that flaws[citation needed] in most major programming languages (e.g. C++, Java, Delphi, and Smalltalk) drove the fundamentals of the Common Language Runtime (CLR), which, in turn, drove the design of the C# language itself.

James Gosling, who created the Java programming language in 1994, and Bill Joy, a co-founder of Sun Microsystems, the originator of Java, called C# an "imitation" of Java; Gosling further claimed that "[C# is] sort of Java with reliability, productivity and security deleted."[15][16] Klaus Kreft and Angelika Langer (authors of a C++ streams book) stated in a blog post that "Java and C# are almost identical programming languages. Boring repetition that lacks innovation,"[17] "Hardly anybody will claim that Java or C# are revolutionary programming languages that changed the way we write programs," and "C# borrowed a lot from Java - and vice versa. Now that C# supports boxing and unboxing, we'll have a very similar feature in Java."[18] In July 2000, Anders Hejlsberg argued that C# is "not a Java clone" and is "much closer to C++" in its design.[19]

Since the release of C# 2.0 in November 2005, the C# and Java languages have evolved on increasingly divergent trajectories, becoming somewhat less similar. One of the first major departures came with the addition of generics to both languages, with vastly different implementations. C# makes use of reification to provide "first-class" generic objects that can be used like any other class, with code generation performed at class-load time.[20] By contrast, Java's generics are essentially a language syntax feature, and they do not affect the generated byte code, because the compiler performs type erasure on the generic type information after it has verified its correctness.[21]

Furthermore, C# has added several major features to accommodate functional-style programming, culminating in the LINQ extensions released with C# 3.0 and its supporting framework of lambda expressions, extension methods, and anonymous types.[22] These features enable C# programmers to use functional programming techniques, such as closures, when it is advantageous to their application. The LINQ extensions and the functional imports help developers reduce the amount of "boilerplate" code that is included in common tasks like querying a database, parsing an xml file, or searching through a data structure, shifting the emphasis onto the actual program logic to help improve readability and maintainability.[23]

C# used to have a mascot called Andy (named after Anders Hejlsberg). It was retired on Jan 29, 2004.[24]

C# was originally submitted for review to the ISO subcommittee JTC 1/SC 22[25] under ISO/IEC 23270:2003,[26] which is now withdrawn. It was then approved under ISO/IEC 23270:2006.[27]

Versions[edit]