However, the language specification does not state the code generation requirements of the compiler: that is, it does not state that a C compiler must target a Common Language Runtime, or generate Common Intermediate Language CIL , or generate any other specific format. Typing Edit C supports strongly typed implicit variable declarations with the keyword var, and implicitly typed arrays with the keyword new followed by a collection initializer. C supports a strict Boolean data type , bool. Statements that take conditions, such as while and if, require an expression of a type that implements the true operator, such as the Boolean type. The only implicit conversions by default are those that are considered safe, such as widening of integers. This is enforced at compile-time, during JIT , and, in some cases, at runtime.
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However, the language specification does not state the code generation requirements of the compiler: that is, it does not state that a C compiler must target a Common Language Runtime, or generate Common Intermediate Language CIL , or generate any other specific format.
Typing Edit C supports strongly typed implicit variable declarations with the keyword var, and implicitly typed arrays with the keyword new followed by a collection initializer. C supports a strict Boolean data type , bool.
Statements that take conditions, such as while and if, require an expression of a type that implements the true operator, such as the Boolean type. The only implicit conversions by default are those that are considered safe, such as widening of integers.
This is enforced at compile-time, during JIT , and, in some cases, at runtime. No implicit conversions occur between Booleans and integers, nor between enumeration members and integers except for literal 0, which can be implicitly converted to any enumerated type.
Enumeration members are placed in their own scope. The C language does not allow for global variables or functions. All methods and members must be declared within classes.
Static members of public classes can substitute for global variables and functions. Metaprogramming Edit Metaprogramming via C attributes is part of the language. Methods and functions Edit A method in C is a member of a class that can be invoked as a function a sequence of instructions , rather than the mere value-holding capability of a class property. Certain specific kinds of methods, such as those that simply get or set a class property by return value or assignment, do not require a full signature, but in the general case, the definition of a class includes the full signature declaration of its methods.
Synchronized ], and has support for mutually-exclusive locks via the keyword lock. Property Edit C provides properties as syntactic sugar for a common pattern in which a pair of methods, accessor getter and mutator setter encapsulate operations on a single attribute of a class. Namespaces can be imported with the "using" syntax. Most object access is done through safe object references, which always either point to a "live" object or have the well-defined null value; it is impossible to obtain a reference to a "dead" object one that has been garbage collected , or to a random block of memory.
Code that is not marked as unsafe can still store and manipulate pointers through the System. IntPtr type, but it cannot dereference them. Managed memory cannot be explicitly freed; instead, it is automatically garbage collected. Garbage collection addresses the problem of memory leaks by freeing the programmer of responsibility for releasing memory that is no longer needed. Exception Edit Checked exceptions are not present in C in contrast to Java.
This has been a conscious decision based on the issues of scalability and versionability. When implementing multiple interfaces that contain a method with the same signature, i. However, unlike Java , C supports operator overloading. NET Framework. Object class. For example, every type inherits a ToString method. Categories of data types Edit CTS separates data types into two categories:  Reference types Value types Instances of value types do not have referential identity nor referential comparison semantics - equality and inequality comparisons for value types compare the actual data values within the instances, unless the corresponding operators are overloaded.
Value types are derived from System. ValueType, always have a default value, and can always be created and copied. Some other limitations on value types are that they cannot derive from each other but can implement interfaces and cannot have an explicit default parameterless constructor. Examples of value types are all primitive types, such as int a signed bit integer , float a bit IEEE floating-point number , char a bit Unicode code unit , and System.
DateTime identifies a specific point in time with nanosecond precision. Other examples are enum enumerations and struct user defined structures.
In contrast, reference types have the notion of referential identity - each instance of a reference type is inherently distinct from every other instance, even if the data within both instances is the same.
This is reflected in default equality and inequality comparisons for reference types, which test for referential rather than structural equality, unless the corresponding operators are overloaded such as the case for System. In general, it is not always possible to create an instance of a reference type, nor to copy an existing instance, or perform a value comparison on two existing instances, though specific reference types can provide such services by exposing a public constructor or implementing a corresponding interface such as ICloneable or IComparable.
Examples of reference types are object the ultimate base class for all other C classes , System. String a string of Unicode characters , and System. Array a base class for all C arrays. Both type categories are extensible with user-defined types. Boxing and unboxing Edit Boxing is the operation of converting a value-type object into a value of a corresponding reference type.
Unboxing is the operation of converting a value of a reference type previously boxed into a value of a value type. A boxed object of type T can only be unboxed to a T or a nullable T. Libraries Edit The C specification details a minimum set of types and class libraries that the compiler expects to have available. In addition to the standard CLI specifications, there are many commercial and community class libraries that build on top of the.
NET framework libraries to provide additional functionality. WriteLine "Hello, world! Each line has a purpose: using System; The above line imports all types in the System namespace. For example, the Console class used later in the source code is defined in the System namespace, meaning it can be used without supplying the full name of the type which includes the namespace. Everything between the following pair of braces describes Program.
NET runtime calls the Main method. Note: Main may also be called from elsewhere, like any other method, e. The static keyword makes the method accessible without an instance of Program. Otherwise, the program would require an instance, but any instance would require a program. To avoid that irresolvable circular dependency , C compilers processing console applications like that above report an error if there is no static Main method.
The void keyword declares that Main has no return value. Console is a static class in the System namespace. It provides an interface to the standard input, output, and error streams for console applications. The program calls the Console method WriteLine, which displays on the console a line with the argument, the string "Hello, world!
Show "Hello, World! WriteLine "Is almost the same argument! Another useful library is the System. Drawing library, which is used to programmatically draw images. For example: using System; using System. FromFile "Image. This process usually takes 6—9 months. The C language definition and the CLI are standardized under ISO and Ecma standards that provide reasonable and non-discriminatory licensing protection from patent claims.
Microsoft has agreed not to sue open source developers for violating patents in non-profit projects for the part of the framework that is covered by the OSP. The compiler, which is entirely written in managed code C , has been opened up and functionality surfaced as APIs. It is thus enabling developers to create refactoring and diagnostics tools. NET class libraries : The Mono project provides an open-source C compiler, a complete open-source implementation of the Common Language Infrastructure including the required framework libraries as they appear in the ECMA specification, and a nearly complete implementation of the Microsoft proprietary.
NET class libraries up to. NET 3. As of Mono 2. NET 2. NET Framework distribution. Xamarin provides tools to develop cross-platform applications for common mobile and desktop operating systems, using C as a codebase and compiling to native code.
The C# Programming Language
Data and OO? See www. Microsoft people these days, just try to solve everything with new programming languages, or exotic syntaxes, etc I want issues solved not arisen, by my programming languages. Most problems people are facing today will not be solved by new languages nor mixing syntaxes, and I must say that the idea of C 3. Still, if you think about it for a little wile, that means new and esoteric syntax to be learned, the first version will probably be very limited, it will be very messy, and of course a new version of SQL server will have to be adopted, a new standard will have to be approved so that the other SQL database vendors can be compatible, etc
Stay safe, friends. Learn to code from home. Use our free 2, hour curriculum. C was developed by Anders Hejlsberg and his development team at Microsoft and is currently on version 7. C has its roots in the family of C languages.