Dot net
NET (pronounced dot net) is a framework that provides a programming guidelines that can be used to develop a wide range of applications–––from web to mobile to Windows-based applications. The . NET framework can work with several programming languages such as C#, VB.NET, C++ and F#.
Features of .NET Framework
• It is a platform neutral framework.
• It is a layer between the operating system and the programming language.
• It supports many programming languages, including VB.NET, C# etc.
• .NET provides a common set of class libraries, which can be accessed from any .NET based programming language. There will not be separate set of classes and libraries for each language. If you know anyone .NET language, you can write code in any .NET language.
• In future versions of Windows, .NET will be freely distributed as part of operating system and users will never have to install .NET separately.
Application Development and Execution
Developing application:
Since Microsoft .NET is a Multilanguage platform then any.NET based language can be chosen to develop applications. Comfort ability of application programmers, specific requirement of applications may be the major factors in selection of language.
Choosing a Compiler
According to the language we can choose its run time aware compiler for .NET platform. Because it is a Multilanguage execution environment, the runtime supports a wide variety of data types and language features.
Compiling to MSIL
When compiling your source code, the compiler translates it into an intermediate code represented in Microsoft intermediate language (MSIL). Before code Can be run, MSIL code must be converted to CPU-specific code, usually by a just-in-time (JIT) compiler. When a compiler produces MSIL, it also produces metadata. Metadata includes following information .
• Description of the types in your code, including the definition of each type,
• The signatures of each type's members,
• The members that your code references,
• Other data that the runtime uses at execution time.
The MSIL and metadata are contained in a portable executable (PE) file that is based on and extends the published Microsoft PE and common object file format (COFF) used historically for executable content. This file format, which accommodates MSIL or native code as well as metadata, enables the operating system to recognize common language runtime images.
Net Framework Design Principle
The following design principles of the .Net framework is what makes it very relevant to create .Net based applications.
- Interoperability - The .Net framework provides a lot of backward support. Suppose if you had an application built on an older version of the .Net framework, say 2.0. And if you tried to run the same application on a machine which had the higher version of the .Net framework, say 3.5. The application would still work. This is because with every release, Microsoft ensures that older framework versions gel well with the latest version.
- Portability- Applications built on the .Net framework can be made to work on any Windows platform. And now in recent times, Microsoft is also envisioning to make Microsoft products work on other platforms, such as iOS and Linux.
- Security - The .NET Framework has a good security mechanism. The inbuilt security mechanism helps in both validation and verification of applications. Every application can explicitly define their security mechanism. Each security mechanism is used to grant the user access to the code or to the running program.
- Memory management - The Common Language runtime does all the work or memory management. The .Net framework has all the capability to see those resources, which are not used by a running program. It would then release those resources accordingly. This is done via a program called the "Garbage Collector" which runs as part of the .Net framework.The garbage collector runs at regular intervals and keeps on checking which system resources are not utilized, and frees them accordingly.
- Simplified deployment - The .Net framework also have tools, which can be used to package applications built on the .Net framework. These packages can then be distributed to client machines. The packages would then automatically install the application.
