.NET Framework
.NET is a "Software Platform". It is a language-neutral environment for developing rich .NET experiences and building applications that can easily and securely operate within it. When developed applications are deployed, those applications will target .NET and will execute wherever .NET is implemented instead of targeting a particular Hardware/OS combination. The components that make up the .NET platform are collectively called the .NET Framework.
The .NET Framework is a managed, type-safe environment for developing and executing applications. The .NET Framework manages all aspects of program execution, like, allocation of memory for the storage of data and instructions, granting and denying permissions to the application, managing execution of the application and reallocation of memory for resources that are not needed.
The .NET Framework is designed for cross-language compatibility. Cross-language compatibility means, an application written in Visual Basic .NET may reference a DLL file written in C# (C-Sharp). A Visual Basic .NET class might be derived from a C# class or vice versa.
The .NET Framework consists of two main components:
Common Language Runtime (CLR)
Class Libraries
Common Language Runtime (CLR)
The CLR is described as the "execution engine" of .NET. It provides the environment within which the programs run. It's this CLR that manages the execution of programs and provides core services, such as code compilation, memory allocation, thread management, and garbage collection. Through the Common Type System (CTS), it enforces strict type safety, and it ensures that the code is executed in a safe environment by enforcing code access security. The software version of .NET is actually the CLR version.
Working of the CLR
When the .NET program is compiled, the output of the compiler is not an executable file but a file that contains a special type of code called the Microsoft Intermediate Language (MSIL), which is a low-level set of instructions understood by the common language run time. This MSIL defines a set of portable instructions that are independent of any specific CPU. It's the job of the CLR to translate this Intermediate code into a executable code when the program is executed making the program to run in any environment for which the CLR is implemented. And that's how the .NET Framework achieves Portability. This MSIL is turned into executable code using a JIT (Just In Time) complier. The process goes like this, when .NET programs are executed, the CLR activates the JIT complier. The JIT complier converts MSIL into native code on a demand basis as each part of the program is needed. Thus the program executes as a native code even though it is compiled into MSIL making the program to run as fast as it would if it is compiled to native code but achieves the portability benefits of MSIL.
Class Libraries
Class library is the second major entity of the .NET Framework which is designed to integrate with the common language runtime. This library gives the program access to runtime environment. The class library consists of lots of prewritten code that all the applications created in VB .NET and Visual Studio .NET will use. The code for all the elements like forms, controls and the rest in VB .NET applications actually comes from the class library.
Common Language Specification (CLS)
If we want the code which we write in a language to be used by programs in other languages then it should adhere to the Common Language Specification (CLS). The CLS describes a set of features that different languages have in common. The CLS defines the minimum standards that .NET language compilers must conform to, and ensures that any source code compiled by a .NET compiler can interoperate with the .NET Framework.
Some reasons why developers are building applications using the .NET Framework:
- Improved Reliability
- Increased Performance
- Developer Productivity
- Powerful Security
- Integration with existing Systems
- Ease of Deployment
- Mobility Support
- XML Web service Support
- Support for over 20 Programming Languages
- Flexible Data Access
Minimum System Requirements to Install and Use Visual Studio .NET
The minimum requirements are:
RAM: 256 MB (Recommended)
Processor: Pentium II 450 MHz
Operating System: Windows 2000 or Windows XP
Hard Disk Space: 3.5 GB (Includes 500 MB free space on disk)
.NET Framework and Languages
As mentioned on the .NET Framework page, .NET Framework is designed for cross-language compatibility.
Cross-language compatibility means .NET components can interact with each other irrespective of the languages they are written in. An application written in VB .NET can reference a DLL file written in C# or a C# application can refer to a resource written in VC++, etc. This language interoperability extends to Object-Oriented inheritance.
This cross-language compatibility is possible due to common language runtime. As you read on the .NET Framework page, when the .NET program is compiled, the output of the compiler is not an executable file but a file that contains a special type of code called the Microsoft Intermediate Language (MSIL). This MSIL is a
low-level language which is designed to be read and understood by the common language runtime. Because all .NET executables exist as IL, they can freely operate. The Common Language Specification defines the minimum standards that .NET language compliers must confirm to. Thus, any code compiled by a .NET complier can interoperate with the .NET Framework.
The Common Type System (CTS) defines the rules concerning data types and ensures that code is executed in a safe environment. Since all .NET applications are converted to IL before execution all primitive data types are represented as .NET types. This means that, a VB Integer and a C# int are both represented in IL code as System.Int32. Because both the languages use a common and interconvertible type system, it is possible to transfer data between components and avoid time-consuming conversions.
Languages supported by .NET Framework
The table below lists all the languages supported by the .NET Framework and describes those languages. The languages listed below are supported by the .NET Framework upto the year 2003. In future there may be other languages that the .NET Framework might support.
| Language | Description/Usage |
| APL | APL is one of the most powerful, consistent and concise computer programming languages ever devised. It is a language for describing procedures in the processing of information. It can be used to describe mathematical procedures having nothing to do with computers or to describe the way a computer works. |
| C++ | C++ is a true OOP. It is one of the early Object-Oriented programming languages. C++ derives from the C language.
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| C# | C# called as C Sharp is a full fledged Object-Oriented programming language from Microsoft built into the .NET Framework. First created in the late 1990’s was part of Microsoft’s whole .NET strategy. |
| Cobol | COBOL (Common Business Oriented Language) was the first widely-used high-level programming language for business applications. It is considered as a programming language to have more lines of code than any other language. |
| Component Pascal | Component Pascal is a Pascal derived programming language that is specifically designed for programming software components. |
| Curriculum | No information. |
| Eiffel | Eiffel is an Object-Oriented (OO) programming language which emphasizes the production of robust software. Eiffel is strongly statically typed mature Object-Oriented language with automatic memory management. |
| | Forth is a programming language and programming environment. It features both interactive execution of commands (making it suitable as a shell for systems that lack a more formal operating system), as well as the ability to compile sequences of commands into threaded code for later execution. |
| Fortran | Acronym for Formula Translator, Fortran is one of the oldest high-level programming languages that is still widely used in scientific computing because of its compact notation for equations, ease in handling large arrays, and huge selection of library routines for solving mathematical problems efficiently. |
| Haskell | Haskell is a computer programming language that is a polymorphicly typed, lazy, purely functional language, quite different from most other programming languages. It is a wide-spectrum language, suitable for a variety of applications. It is particularly suitable for programs which need to be highly modifiable and maintainable. |
| Java Language | The Java language is one of the most powerful
|
| Microsoft JScript | Microsoft JScript is the Microsoft implementation of the ECMA 262 language specification. JScript is an interpreted, object-based scripting language. It has fewer capabilities than full-fledged Object-Oriented languages like C++ but is more than sufficiently powerful for its intended purposes. |
| Mercury | Mercury is a new logic/functional programming language, which combines the clarity and expressiveness of declarative programming with advanced static analysis and error detection features. Its highly optimized execution algorithm delivers efficiency far in excess of existing logic programming systems, and close to conventional programming systems. Mercury addresses the problems of large-scale program development, allowing modularity, separate compilation, and numerous optimization/time trade-offs. |
| Mondrian | Mondrian is a simple functional scripting language for Internet applications. It is a functional language specifically designed to
|
| Oberon | Oberon is a programming language very much like Modula-2 in syntax but with several interesting features. It's based on OOP concepts and provides a Windows-based graphical user interface. |
| Oz | Oz is a high-level programming language that combines constraint inference with concurrency. Oz is dynamically typed and has first-class procedures, classes, objects, exceptions and sequential threads synchronizing over a constraint store. It supports finite domain and feature constraints and has powerful primitives for programming constraint inference engines at a high level. |
| Pascal | Principle objectives for Pascal were for the language to be efficent to implement and run, allow for the development of well structured and well organized programs, and to serve as a vehicle for the teaching of the important concepts of computer programming. The Prime area of application that Pascal entails is the learning environment. This language was not really developed to be used for anything other than teaching students the basics of programming as it was originally developed for this purpose. |
| Perl | Practical Extraction and Report Language, Perl, is a language optimized for scanning arbitrary text files, extracting information from those text files, and printing reports based on that information. It's also a good language for many system management tasks. |
| Python | Python is an interpreted, interactive, Object-Oriented programming language. Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. |
| RPG | Report Program Generator, RPG, is used for generation of reports from data files, including matching record and sub-total reports. RPG is one of the few languages created for punch card machines that is still in common use today. RPG or RPG IV is a native programming language for IBM's iSeries minicomputer system. |
| Scheme | Scheme is a statically scoped programming language. It was designed to have an exceptionally clear and simple semantics and few different ways to form expressions. A wide variety of programming paradigms, including imperative, functional, and message passing styles, find convenient expression in Scheme. |
| Small Talk | SmallTalk is an expressive language that uses a simple sub set of human languages, nouns and verbs. Smalltalk was the first, and remains one of the few, pure object systems, which simply means that everything in a Smalltalk program is an object. Smalltalk is generally recognized as the second Object Programming Language (OPL). |
| Standard ML | Standard ML is a safe, modular, strict, functional, polymorphic programming language with compile-time type checking and type inference, garbage collection, exception handling, immutable data types and updatable references, abstract data types, and parametric modules. It has efficient implementations and a formal definition with a proof of soundness. |
| Microsoft Visual Basic | Visual Basic is a "visual programming" environment for developing Windows applications. Visual Basic makes it possible to develop complicated applications very quickly. This site is all about Visual Basic. |
.NET Framework Advantages
The .NET Framework offers a number of advantages to developers. The following paragraphs describe them in detail.
Consistent Programming Model
Different programming languages have different approaches for doing a task. For example, accessing data with a VB 6.0 application and a VC++ application is totally different. When using different programming languages to do a task, a disparity exists among the approach developers use to perform the task. The difference in techniques comes from how different languages interact with the underlying system that applications rely on.
With .NET, for example, accessing data with a VB .NET and a C# .NET looks very similar apart from slight syntactical differences. Both the programs need to import the System.Data namespace, both the programs establish a connection with the database and both the programs run a query and display the data on a data grid. The VB 6.0 and VC++ example mentioned in the first paragraph explains that there is more than one way to do a particular task within the same language. The .NET example explains that there's a unified means of accomplishing the same task by using the .NET Class Library, a key component of the .NET Framework.
The functionality that the .NET Class Library provides is available to all .NET languages resulting in a consistent object model regardless of the programming language the developer uses.
Direct Support for Security
Developing an application that resides on a local machine and uses local resources is easy. In this scenario, security isn't an issue as all the resources are available and accessed locally. Consider an application that accesses data on a remote machine or has to perform a privileged task on behalf of a nonprivileged user. In this scenario security is much more important as the application is accessing data from a remote machine.
With .NET, the Framework enables the developer and the system administrator to specify method level security. It uses industry-standard protocols such as TCP/IP, XML, SOAP and HTTP to facilitate distributed application communications. This makes distributed computing more secure because .NET developers cooperate with network security devices instead of working around their security limitations.
Simplified Development Efforts
Let's take a look at this with Web applications. With classic ASP, when a developer needs to present data from a database in a Web page, he is required to write the application logic (code) and presentation logic (design) in the same file. He was required to mix the ASP code with the HTML code to get the desired result.
ASP.NET and the .NET Framework simplify development by separating the application logic and presentation logic making it easier to maintain the code. You write the design code (presentation logic) and the actual code (application logic) separately eliminating the need to mix HTML code with ASP code. ASP.NET can also handle the details of maintaining the state of the controls, such as contents in a textbox, between calls to the same ASP.NET page.
Another advantage of creating applications is debugging. Visual Studio .NET and other third party providers provide several debugging tools that simplify application development. The .NET Framework simplifies debugging with support for Runtime diagnostics. Runtime diagnostics helps you to track down bugs and also helps you to determine how well an application performs. The .NET Framework provides three types of Runtime diagnostics: Event Logging, Performance Counters and Tracing.
Easy Application Deployment and Maintenance
The .NET Framework makes it easy to deploy applications. In the most common form, to install an application, all you need to do is copy the application along with the components it requires into a directory on the target computer. The .NET Framework handles the details of locating and loading the components an application needs, even if several versions of the same application exist on the target computer. The .NET Framework ensures that all the components the application depends on are available on the computer before the application begins to execute.
.NET Framework Advantages
The .NET Framework offers a number of advantages to developers. The following paragraphs describe them in detail.
Consistent Programming Model
Different programming languages have different approaches for doing a task. For example, accessing data with a VB 6.0 application and a VC++ application is totally different. When using different programming languages to do a task, a disparity exists among the approach developers use to perform the task. The difference in techniques comes from how different languages interact with the underlying system that applications rely on.
With .NET, for example, accessing data with a VB .NET and a C# .NET looks very similar apart from slight syntactical differences. Both the programs need to import the System.Data namespace, both the programs establish a connection with the database and both the programs run a query and display the data on a data grid. The VB 6.0 and VC++ example mentioned in the first paragraph explains that there is more than one way to do a particular task within the same language. The .NET example explains that there's a unified means of accomplishing the same task by using the .NET Class Library, a key component of the .NET Framework.
The functionality that the .NET Class Library provides is available to all .NET languages resulting in a consistent object model regardless of the programming language the developer uses.
Direct Support for Security
Developing an application that resides on a local machine and uses local resources is easy. In this scenario, security isn't an issue as all the resources are available and accessed locally. Consider an application that accesses data on a remote machine or has to perform a privileged task on behalf of a nonprivileged user. In this scenario security is much more important as the application is accessing data from a remote machine.
With .NET, the Framework enables the developer and the system administrator to specify method level security. It uses industry-standard protocols such as TCP/IP, XML, SOAP and HTTP to facilitate distributed application communications. This makes distributed computing more secure because .NET developers cooperate with network security devices instead of working around their security limitations.
Simplified Development Efforts
Let's take a look at this with Web applications. With classic ASP, when a developer needs to present data from a database in a Web page, he is required to write the application logic (code) and presentation logic (design) in the same file. He was required to mix the ASP code with the HTML code to get the desired result.
ASP.NET and the .NET Framework simplify development by separating the application logic and presentation logic making it easier to maintain the code. You write the design code (presentation logic) and the actual code (application logic) separately eliminating the need to mix HTML code with ASP code. ASP.NET can also handle the details of maintaining the state of the controls, such as contents in a textbox, between calls to the same ASP.NET page.
Another advantage of creating applications is debugging. Visual Studio .NET and other third party providers provide several debugging tools that simplify application development. The .NET Framework simplifies debugging with support for Runtime diagnostics. Runtime diagnostics helps you to track down bugs and also helps you to determine how well an application performs. The .NET Framework provides three types of Runtime diagnostics: Event Logging, Performance Counters and Tracing.
Easy Application Deployment and Maintenance
The .NET Framework makes it easy to deploy applications. In the most common form, to install an application, all you need to do is copy the application along with the components it requires into a directory on the target computer. The .NET Framework handles the details of locating and loading the components an application needs, even if several versions of the same application exist on the target computer. The .NET Framework ensures that all the components the application depends on are available on the computer before the application begins to execute.
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