Visual C#

C#is an object-oriented programming language developed by Microsoft as part of their .NET initiative, and later approved as a standard by ECMA and ISO. C# has a procedural, object-oriented syntax based on C++ that includes aspects of several other programming languages .

C# 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 regards to memory and processing power requirements, the language was not intended to compete directly on performance and size with C or assembly language.

C#'s principal designer, and lead architect at Microsoft, is Anders Hejlsberg. His previous experience in programming language and framework design (Visual J++, Borland Delphi, Turbo Pascal) can be readily seen in the syntax of the C# language, as well as throughout the CLR (Common Language Runtime) core. He can be cited in interviews and technical papers as stating flaws in most major programming languages, for example, C++, Java, Delphi, Smalltalk, were what drove the fundamentals of the CLR, which, in turn, drove the design of the C# programming language itself. His expertise can be seen in C#. Some argue that C# shares roots in other languages, as purported by programming language history chart.

C# has a unified type system. This unified type system is called Common Type System (CTS).A unified type system implies that all types, including primitives such as integers, are subclasses of the System.Object class. For example, every type inherits a ToString() method. For performance reasons, primitive types (and value types in general) are internally allocated on the stack.

CTS separates datatypes into two categories:

• Value Type
• Reference Type

While value types are those in which the value itself is stored by allocating memory on the stack, reference types are those in which only the address to the location where the value is present, is stored. Value types include integers (short, long), floating-point numbers (float, double), decimal (a base 10 number), structures, enumerations, booleans and characters while reference types include objects, strings, classes, interfaces and delegates.

C# also allows the programmer to create user-defined value types, using the struct keyword. From the programmer's perspective, they can be seen as lightweight classes. Unlike regular classes, and like the standard primitives, such value types are allocated on the stack rather than on the heap. They can also be part of an object (either as a field or boxed), or stored in an array, without the memory indirection that normally exists for class types. Structs also come with a number of limitations. Because structs have no notion of a null value and can be used in arrays without initialization, they are implicitly initialized to default values (normally by filling the struct memory space with zeroes, but the programmer can specify explicit default values to override this). The programmer can define additional constructors with one or more arguments. This also means that structs lack a virtual method table, and because of that (and the fixed memory footprint), they cannot allow inheritance (but can implement interfaces).