. NET Framework version Resolution __.NET

The. NET new technology is constantly being refurbished, the. NET Framework version has been starting from 1.0, after 1.1, 2.0, 3.0, and now to 3.5. Many people exclaimed: "Change too fast, we have just learned one, the next came again, it seems that there is always something to learn." In fact, when you fall in love with the IT industry at that moment, there should be "live to old, learn to old" mentally prepared. In the IT industry, it also confirms the "Want to say love you not easy" this fashionable popular phrase.

The. NET Framework is constantly updated with old bottles of new wine or new bottles of old wine. The answer seems to be more the latter. And look at the following formula:

The. NET Framework 3.5 = . NET Framework 3.0 +. NET Framework 3.0 SP1
. NET Framework 3.0 = . NET Framework 2.0 +. NET Framework 2.0 SP1 + WPF + WCF + WF + WCS

The. NET Framework version 3.5 is based on the. NET Framework version 2.0 and the. NET Framework 3.0, including the. NET Framework 2.0 and 3.0 Service packs.

The. NET Framework 2.0 SP1: It updates the assemblies that are contained in the. NET Framework 2.0.
The. NET Framework 3.0 also contains the necessary assemblies for the technologies introduced in the. NET Framework 3.0. For example, WPF, etc.
The. NET Framework 3.0 Service Pack 1, which updates the assemblies (Presentationframework.dll,presentationcore.dll, etc.) introduced in the. NET Framework 3.0.

Applications use the same assembly whether they are for the. NET Framework 2.0, 3.0, or version 3.5.
For example, for applications that use WPF and for the. NET Framework 3.0, the mscorlib assembly instance used is the same as for applications using Windows forms and for the. NET Framework 2.0. If the. NET Framework 2.0 SP1 is installed on your computer, mscorlib.dll has been updated, and all two applications will use the updated version of mscorlib.dll.

So, someone has summed up this:

. NET 3.0 =. NET 2.0 SP 1 with WCF, WPF, WF and WCS
. NET 3.5 =. NET 2.0 SP 2 with LINQ, C # 3.0, WCF 2.0, WPF 2.0, WF 2.0 and ASP.net Ajax

It is worth mentioning that the relationships between versions 2.0, 3.0, and 3.5 of the. NET Framework are different from those of the 1.0, 1.1, and 2.0 editions. The . NET Framework versions 1.0, 1.1, and 2.0 are completely independent of each other, and you can exist on that computer for any version of it, regardless of whether there are other versions on the computer. When versions 1.0, 1.1, and 2.0 are on the same computer, each version has its own common language runtime, class library, compiler , and so on. That is, an application can choose between 1.0, 1.1, or 2.0 versions.

. NET version comparison table

. NET Packaged version	1.0	1.1	2.0	3.0	3.5
CLR version	1.0	1.1	2.0	2.0	2.0
C # Compiler version	1.0	1.1	2.0	2.0	3.0
vb Compiler version	7.0	7.1	8.0	8.0	9.0

Version compatibility

For version compatibility, the following is an explanation of MSDN:
The. NET Framework support for backward and forward compatibility is version-dependent. The. NET Framework supports backward and forward compatibility only for applications created with version 1.1. In applications created with version 2.0, the. NET Framework does not support forward compatibility。 In the context of the. NET Framework, backward compatibility means that applications created with earlier versions of the. NET Framework can run on a higher version. In contrast, forward compatibility means that applications created with a later version of the. NET Framework can run on earlier versions.

the. NET Framework provides high levels of backward compatibility support . For example, most applications created with version 1.0 will run on version 1.1, and applications created with version 1.1 will run on version 2.0. Only for version 1.1, the. NET Framework also supports forward compatibility. However, for forward compatibility, you may need to modify your application to make the application run as expected. applications created with version 2.0 will not run on earlier versions of the. NET Framework . For backward and forward compatibility, changes to the. NET Framework that can improve security, correctness, and functionality may also cause compatibility issues.

Related articles: Introduction to Features in. NET Framework 3.5 (1)