. NET cognition and theoretical summary

One. NET is what

Some developers feel that. NET is a development tool, or a platform, a software development environment. I feel that these understandings are not completely, personally feel,. NET should be a concept, a strategy and a dream for Microsoft.

Microsoft for. NET definition: Microsoft. NET is the Microsoft XML Web services platform, and XML Web services allows applications to communicate and share data over the Internet, regardless of the operating system, device, or programming language used, M The icrosoft. NET platform provides the creation of XML Web services and integrates them together.

Popular understanding is: Microsoft. NET is a group of software products, technologies, or services that provide seamless connectivity to information, people, systems, and devices at the core of Microsoft Web services. What we generally say. NET refers to the. NET Framework, Visual Studio.NET, and developed applications such as ASP. NET Framework is a development and execution environment, Allows different programming languages and libraries to seamlessly combine to create Windows-based applications, easily create, manage, deploy, and integrate with other network systems.

As the architecture of the. NET Framework:

can be understood. NET Development framework is a few of the main components:

• The core and foundation of the entire development framework are the common language runtime (CLR) and the set of base class libraries (BCL) it provides;
• In the development of technology,. NET provides a new access to the database technology, as well as the development of technology, ASP. Winform;
• In the development language, the. NET support VB, VC + +, C #, JS and many other languages, Visual Studio is to support these development language development tools.

The. NET framework is a hardware-independent program execution platform, and we use C, C + +, Delphi language developed programs compiled by the hardware can recognize the machine code, and developed. NET application is compiled not by machine code, but by the. NET Framework-recognized intermediate language code MSIL (Microsoft intermediate Language), which is not dedicated to any one operating system and therefore can be cross-lingual.

When the program runs, it is first compiled by the JIT (just-in-time) compiler into native code dedicated to the current operating system and the target machine structure two times, and then executed on the computer through the managed CLR environment and base Class library, so we developed. NET application must have the. NET Framework installed to run.

. NET application runs as follows:

Application-(compiled) assembly (MSIL)-(JIT-compiled)-native code

(1) use. NET compatible language (C #) to develop an application, and then the application is compiled into intermediate language (MSIL), which is stored in the assembly;

(2) When executing code, you must first use the JIT compiler to compile the cost machine code in the intermediate language. The JIT compiler knows exactly what type of processor The program is running on, and can use the features provided by the processor or specific machine instructions to optimize the final executable code;

(3) Run native code in a managed CLR environment.

Use metaphor to deepen understanding:

. NET is like the entire Network and service operation platform of China Mobile, the. NET Framework is the infrastructure that supports the platform, and the software is developed to run various services under this platform, such as voice calls, SMS, MMS, etc. Any service requires the support of a mobile network, just as the software we develop requires the support of the. NET framework to run.

Two. NET Features

. NET has the following major features:

1, once compiled, run everywhere.

The development of the program should be compiled with an intermediate code (MSIL) of the Assembly, as to how to run, is to the. NET framework of the JIT compiler to complete the intermediate code into a recognizable machine code. As a result, applications can run wherever the. NET Framework supports it.

2, the programming language sinks into a family, does not divide you me.

Now there are many programming languages, such as VB, C #, J #, Delphi, Java and so on. A common Language system CLS (Common Language System) is designed in the. NET framework and defines a number of standard data types, when translated into intermediate-language MSIL , the data types of the various high-level languages are converted to the standard data types in the CLS system. For example, VB. The integer data types in net are converted to system.int32,c# int types are also converted to System.Int32 so that different languages can be converted through the CLS to each other and can invoke methods and class libraries that are not written in languages.

3, Memory automatic management, peace of mind programming.

The biggest impact of the CLR is its memory management capabilities, which provide the application with a high-performance garbage collection mechanism GC (garbage Collector). The GC automatically follows the objects that are manipulated by the application and manages the content.

4, base Class library, make development simple.

Classes are a very important part of the object-oriented design language, and the class libraries in the. NET framework provide a very rich class of classes, such as string processing, database connectivity, file access, and so on, making development simple.

. NET cognition and theory summary