What is the .NET architecture?
Microsoft .NET consists of four major components:
• • • •
Common Language Specification (CLS) – blue in the diagram below Framework Class Library (FCL) – red Common Language Runtime (CLR) – green .NET Tools – yellow
At the base of the diagram in gray is the operating system, which technically can be any platform but typically is Microsoft Windows 2000 or greater, accessed through the Win32 API (Application Programming Interface).
Common Language Specification (CLS)
The CLS is a common platform that integrates code and components from multiple .NET programming languages. In other words, a .NET application can be written in multiple programming languages with no extra work by the developer (though converting code between languages can be tricky). .NET includes new object-oriented programming languages such as C#,Visual Basic .NET, J# (a Java clone) and Managed C++. These languages, plus other experimental languages like F#, all compile to the Common Language Specification and can work together in the same application.
Framework Class Library (FCL)
The FCL is a collection of over 7000 classes and data types that enable .NET applications to read and write files, access databases, process XML, display a graphical user interface, draw graphics, use Web services, etc. The FCL wraps much of the massive, complex Win32 API
into more simple .NET objects that can be used by C# and other .NET programming languages.
Common Language Runtime (CLR)
The CLR is the execution engine for .NET applications and serves as the interface between .NET applications and the operating system. The CLR provides many services such as:
• • • • • • • • • •
Loads and executes code Converts intermediate language to native machine code Separates processes and memory Manages memory and objects Enforces code and access security Handles exceptions Interfaces between managed code, COM objects, and DLLs Provides type-checking Provides code meta data (Reflection) Provides profiling, debugging, etc.
.NET Tools
Visual Studio .NET is Microsoft’s flagship tool for developing Windows software. Visual Studio provides an integrated development environment (IDE) for developers to create standalone Windows applications, interactive Web sites, Web applications, and Web services running on any platform that supports .NET. In addition, there are many .NET Framework tools designed to help developers create, configure, deploy, manage and secure .NET applications and components.
What is the history of .NET?
.NET started as a classic Microsoft FUD operation. In the late 1990s, Microsoft had just successfully fought off a frontal assault on its market dominance by killing the Netscape Web browser with its free Internet Explorer. But Microsoft was facing a host of new challenges, including serious problems with COM, C++, DLL hell, the Web as a platform, security, and strong competition from Java, which was emerging as the go-to language for Web development. Microsoft started building .NET in the late 90s under the name “Next Generation Windows Services” (NGWS). Bill Gates described .NET as Microsoft’s answer to the “Phase 3 Internet environment, where the Internet becomes a platform in its own right, much like the PC has traditionally been… Instead of a world where Internet users are limited
to reading information, largely one screen at a time, the Phase 3 Internet will unite multiple Web sites running on any device, and allow users to read, write and annotate them via speech, handwriting recognition and the like,” Gates said. We are certainly approaching that vision. Microsoft announced .NET to the world in June 2000 and released version 1.0 of the .NET framework in January 2002. Microsoft also labeledeverything .NET including briefly Office to demonstrate its commitment and dominance on this new thing called the Web. But out of that grand FUD campaign emerged the very capable and useful .NET development environment and framework for both the Web and Windows desktop.
What are the benefits of .NET?
.NET provides the best platform available today for delivering Windows software. .NET helps make software better, faster, cheaper, and more secure. .NET is not the only solution for developing Web software— Java on Linux is a serious alternative. But on the Windows desktop, .NET rules. For developers, .NET provides an integrated set of tools for building Web software and services and Windows desktop applications. .NET supports multiple programming languages and Service Oriented Architectures (SOA). For companies, .NET provides a stable, scalable and secure environment for software development. .NET can lower costs by speeding development and connecting systems, increase sales by giving employees access to the tools and information they need, and connect your business to customers, suppliers and partners. For end-users, .NET results in software that’s more reliable and secure and works on multiple devices including laptops, Smartphones and Pocket PCs.
Why are you (this blog author) developing in .NET?
The Mini-Tools developers were impressed with the Microsoft .NET technology and development platform and felt it provided the best
environment with which to build and deliver innovative desktop and Web software for Windows. All of our software is written in C# for .NET on Windows.
Why should I install .NET on my computer?
Because many new software applications require .NET. Having the latest version already installed on your computer enables you run new .NET applications immediately as they become available.
Which versions of .NET are available?
The newest version available today is NET v3.0, but most PC users have v2.0 installed. Although .NET v3.0 is now available, Windows Update is not automatically installing it, hence few people have it. People who purchase new PCs with Windows Vista pre-installed will receive the latest .NET v3.0 but there may be some versioning issues. Microsoft released a beta version of .NET v3.5 in April 2007. Following are the production versions of .NET: Version Name 1.0 1.0 SP1 1.0 SP2 1.0 SP3 1.1 1.1 SP1 2.0 3.0 Version Number 1.0.3705.0 1.0.3705.209 1.0.3705.288 1.0.3705.6018 1.1.4322.573 1.1.4322.2032 2.0.50727.42 3.0.4506.30 Release Date 2002-01-05 2002-03-19 2002-08-07 2004-08-31 2003-04-01 2004-08-30 2005-11-07 2006-11-06
How do I know if I already have .NET?
We have queried your Web browser, and it tells us that you have the following .NET versions installed on your PC (note this only works for Internet Explorer): Another way to check if you have .NET: 1. Click Start on your Windows desktop.
2. Select Control Panel. 3. Double-click Add or Remove Programs. 4. When the Add/Remove window appears, scroll through the list of applications and try to find Microsoft .NET Framework. There you will see which versions of .NET are installed on your PC.
Where can I get .NET?
Microsoft .NET is available as a FREE download from Microsoft.
Why is .NET separate from the Windows operating system?
Another way to ask this question is, "Why doesn't Microsoft ensure every Windows PC has the latest version of .NET installed?" Since .NET is so important to Windows, and Microsoft delivers both .NET and Windows, why doesn't Microsoft simply make .NET part of Windows? Just my theory, but it probably stems from the Sun vs. Microsoft bad blood over Java. Sun and Microsoft got into a legal spat, Microsoft stopped shipping Java with Windows, and so now Java is a separate download for Windows users. As a result, perhaps Microsoft is wary of appearing monopolistic, hence they maintain the .NET Framework as a separate download too. Why is this a problem? Because it is a large file that must be downloaded and installed separately, naturally many people view .NET with suspicion or at least hesitation. And this provides an inconvenience and yet another barrier for a potential customer purchasing our .NET software. So here's my plea: Microsoft, please include the latest version of .NET as an automatic download to every Windows PC as part of the normal Windows Update process. Thank you.