ASP.Net Page-Life-Cycle

ASP.NET Page-Life-Cycle :

Page Life Cycle

ASP.NET Engine

FRAMEWORK_ARCHITECTURE

The .NET Framework provides support to developers to create new application. It consists of all the necessary components to develop and run programs on our computers. some of the components are as follows:

• Common Language Runtime (CLR)
• Common Type System (CTS)
• Assemblies
• Base Class Library
• ASP .NET and ASP.NET AJAX
• ADO.NET
• Windows Forms
• Windows Presentation Foundation (WPF)
• Windows Communication Foundation (WCF)
• LINQ

CLR (Common Languate Runtime) :

CLR is the most prominent component of .NET framework. As the name itself indicates that it is Runtime for the applications that are developed in .NET. It provides a runtime environment to the code and serves several services to the application like memory management, exception handling, security, threading, verification and compilation etc,. We can say in one sentence that “CLR manages code execution at runtime by managing every resource that possibly involved or necessary to complete the task”.

Managed code and Unmanaged code:

Managed Code:

Managed code is the code that is executed directly by the CLR. The applications that are created using managed code will have CLR components like automatic garbage collection type checking. These components will provide platform and language independence to managed code applications. The CLR compiles the applications to Intermediate Language (IL) not to machine language. This intermediate language describes the attribute, classes and methods the code in the assembly.  Intermediate Language is CPU independent, which must be converted to CPU understandable code which will be done by JIT Compiler (Just In Time Compiler) just before execution. Native code is a CPU specific code which is the output of the JIT Compiler that can actually runs in the runtime.

Unmanaged Code :

Unmanaged code can be directly compiled to machine code and  can run on the machine where it has been compiled. since it has no components like memory management and other prominent servies it might get manipulated and may cause harmful issues.

Common Type System ( CTS ) :

The CTS specifies guidelines for using, creating and managing data types at runtime. It is a included module in the runtime environment for supporting multilingual system. Main functions of CTS are as follows

1. Helps in Cross language communication, type safety, and performance efficiency of code providing a framework.
2.  Supports Object-Oriented model for implementation of different programming languages.
3. Provides guidelines for different languages to follow, ensuring proper interaction between objects of different languages.
4. Suooirts primitive data types, such as Byte, Char, Int Boolean that are used in the process of developoment of an application.

Assemblies and Metadata:

Generally an assembly is a unit that consists of four elements manifest, type metadata, IL Code and resources. A metadata is binary info that describes a program, stored in a CLR or in the memory. When compilation is going on a PE File(Portable Executable) the meta data is inserted into a part of file while code converted into IL which will be inserted into other part of file. Metadata describes every attribute we have. While executing the program CLR loads this meta data into memory and find information about all classes and methods needed to execute the application. The description of attributes in the metadata are language neutral, which includes identities like name, version, culture, public key, type of assembly, reference assemblies, permissions, Information about names, visibility, base class, interfaces used, and members.

 Thanks,
Reference MSN,Dotnet4u