In the Windows 7 Enterprise edition with IIS7.
If an application's application pool is .net framework 2.0, can it use a class library written using .net framework 3.5?
Rick
An application pool in IIS is not tied to a particular version of the framework but to a version of the CLR. It can be set to CLR 1.1, CLR 2.0 or 4.0. Because .NET 2.0 and 3.5 use both the same CLR 2.0 you can use a library compiled against .NET 3.5 without any problems.
Related
We have a web forms project that is running on ASP.Net 3.5 and we need to upgrade all the way to 4.7. Telerik controls are involved which I know will need to be upgraded as well. This is a large web application and I know there is not quick solution, but trying to figure out how to get started. Does anyone have any recommendations for such a task.
It depends on the CLR for the .Net framework you are using.
.Net Framework 2.0, 3.0, and 3.5 uses CLR 2.0
.Net Framework 4, 4.5, and 4.5.1 uses CLR 4.0
CLR 3.0 does not exist
An application developed in .Net 2.0 or 3.0 can run in a 3.5 framework because the target CLR is the same
But an application developed in .Net 3.0 will not run in a 4.5 framework because now the target framework is different (CLR 4)
Solution
To configure your application to run on .Net Framework 4 or 4.5:
Create a text file that has the same name as your application, and add the file extension .config. For example, if your application is named abc.exe then your application configuration file must be named abc.exe.config.
Add the element as follows to the application configuration file:
`<configuration>
<startup>
<supportedRuntime version="version"/>
</startup>
</configuration>`
Check framework upgrade guidelines here: https://social.msdn.microsoft.com/Forums/vstudio/en-US/d4c6adee-4dd5-435d-a021-4fd9d4c6f7c0/net-framework-upgrade-from-35-to-471?forum=netfxsetup
We have existing web application which is developed on .Net 3.5 but we wish to now upgrade it to .Net 4.5. But I want to make sure that it runs even on windows 7 OS without .Net framework 4.5. Is that possible with any workarounds?
The simple answer is NO. You'll need to install .NET Framework 4.5.
Microsoft provides a number of command line tools for working with asp.net applications. I haven't had any trouble using these tools. One thing that I can not understand though, is the location of these tools.
Even for applications targeting newer versions of .net, these tools are located in the .net v2 directory. On my machine, that's C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727. Why do these tools not exist in the v3.0 or v3.5 directories? And why do the ones in the older directory work on the newer framework?
This is more of an idle curiosity than required knowledge for me, but I would like to know.
Update:
Thanks for the good answers everyone. These answers raise a new question though. I hope you will forgive me for asking it here, since it is so highly related. If .net 3.5 is really just using the CLR from 2.0, why is 2.0 compatible with Windows 2000, but not 3.5? It would seem to me that if the updates in 3.0 and 3.5 run inside the framework of the earlier version, then they must maintain compatibility with the same platforms as the earlier version too. Why is this wrong?
.NET 3.0 and 3.5 are (basically) just library additions to the 2.0 framework.
The addition of .NET 3.0 didn't mean new compilers or a new CLR. Instead, it's three major new libraries: WCF (Windows Communication Foundation née Indigo), WPF (Windows Presentation Foundation née Avalon) and Windows Workflow or WF.
Basically, remember Framework version != CLR Version. If you configured an IIS Application to use .NET 2.0, you're talking about the 2.0 CLR. WCF Applications use the .NET 2.0 CLR with the new 3.0 WCF libraries.
* .NET Framework 1.x = CLR 1.x
* .NET Framework 2.0 = CLR 2.0
* .NET Framework 3.0 = CLR 2.0
* .NET Framework 3.5 = CLR 2.0 + (C# 3.0 | VB9)
Edit:
To answer your second question, .NET 3.0 and 3.5 have new libraries which reference OS-level features like WPF, which isn't available on Windows 2000. If you write an application in 3.5* but only use functionality and libraries that were also available in 2.0, it can still work on Windows 2000.
*by "in 3.5", we mean write it in Visual Studio 2008 under 3.5 but set your Project Target Framework to 2.0. Scott Hanselman talks about doing this to get ASP.NET MVC to work on .NET 2.0.
It is because the core of .Net has not actually been changed since v2.0. MS marketing types were much derided at the time for forcing the naming scheme in use, where .Net 3, and .Net 3.5 are really just adding additional libraries that run on the .Net 2 core.
Check out Scott Hanselman's blog post for more details.
Because .NET 3.0 and 3.5 are applications of .NET 2.0, not complete, standalone frameworks unto themselves. This is further see in the IIS config, where you only have the option to select .NET 1.0, .NET 1.1, and .NET 2.0. You web.config file will include any .NET 3.0 or .NET 3.5 assemblies as these are written, ultimately, with .NET 2.0 code. More details about that can be seen here: http://www.hanselman.com/blog/HowToSetAnIISApplicationOrAppPoolToUseASPNET35RatherThan20.aspx
Of course, that all changes in .NET 4.0 which will be a completely "new version" of the framework.
v3.0 and v3.5 still uses the v2 DLLs for the core files. Most of the changes are additions to the v2 framework as well as a new compiler for 3.5.
We are developing ASP.NET site in VS.NET 2005. This site is will be hosted on server which has .NET 3.0 installed and in IIS, ASP.NET 2.0 would be selected under ASP.NET tab.
We would use external DLL which is being developed in VS.NET 2008 with .NET 3.0 as taraget framework. Here they are using .NET 3.0 / C# 3.0 features such as Lamda expressions.
Now, the question is,
1) If we were not using this external DLL (.NET 3.0 as taraget framework), which .NET framework version it would use for this site? Since in this case only .NET 2.0 DLLs are referenced, I think it should use 2.0 framework only.
2) In current case where we are using this external DLL (.NET 3.0 as taraget framework), will it load both framework in memory for this website or just highest version i.e. .NET framework 3.0?
3) Are there any side effects in this case because the application (website) DLL would ask loader to load .NET framework 2.0 and one of the extrenal DLL, the main application requires is in .NET 3.0. Is is possible that .NET 2.0 will be loaded first for the application but when application references external DLL, .NET 3.0 framework will be loaded?
4) Is there any difference if
the external DLL developed in .NET 3.0 as taraget framework was refereced as "Add Reference" using VS.NET 2005
the external DLL developed in .NET 3.0 as taraget framework was just copied into bin folder of application (website)
5) If it depends on what features are used in .NET 3.0 framework, please provide details in both cases; when those features used and those features are not used.
.Net 3.0 is an extension of .Net 2.0. There is no "replacement" of the framework DLLs when you use .Net 3.0 because it is composed of the same libraries, plus some additional DLLs for the added functionality. Think of the extra .Net 3.0 DLLs as additional, external functionality that is only loaded as needed.
I am currently aware that ASP.NET 2.0 is out and about and that there are 3.x versions of the .Net Framework.
Is it possible to upgrade my ASP.NET web server to version 3.x of the .Net Framework?
I have tried this, however, when selecting which version of the .Net framwork to use in IIS (the ASP.NET Tab), only version 1.1 and 2.0 show.
Is there a work around?
if I install 3.5 and have IIS setup to use 2.0. I will be able to use 3.5 features?
Yes, that is correct. You have IIS set to 2.0 for both 2.0 and 3.5 sites, as they both run on the same CLR. 3.5 uses a different compile method than 2.0. This is declared in the web.config for the site. See this post for more details on this. But the setup in IIS for both 3.5 and 2.0 ASP.net sites is identical.
Unfortunately, the statement .NET versions can be installed side-by-side, so it won't disrupt any "legacy" apps isn't entirely true. If you install 3.5, it requires 2.0 SP1, which can disrupt legacy applications that uses 2.0 and connects to Oracle database servers.
Sure, download the 3.5 redistributable, install it on the servre, and you're good to go. .NET versions can be installed side-by-side, so it won't disrupt any "legacy" apps.
http://www.microsoft.com/downloads/details.aspx?FamilyId=333325FD-AE52-4E35-B531-508D977D32A6&displaylang=en
GateKiller,
.NET 3.0 and .NET 3.5 did not change the version of the CLR, so "using ASP.NET 3.5" is a more complicated thing that it sounds like it should be at first. In essence, you're still running on the 2.0 CLR, but you're using the C# 3.0 compiler and linking against the 3.5 libraries. It means adding a bunch of stuff to your Web.config file to become an ASP.NET 3.5 project.
Scott Hanselman has an awesome blog post covering the details:
http://www.hanselman.com/blog/HowToSetAnIISApplicationOrAppPoolToUseASPNET35RatherThan20.aspx
The version you are selecting in IIS is the version of the CLR to use. There are only two versions of the CLR. The .NET Framework 3.5 runs on CLR 2.0
The new framework is .Net 3.5, you'll have a new assembly System.Core, + a few more if you use features like Linq
.Net 3.5 comes with the new C#3.0 compiler
ASP.Net is still version 2.0
Lovely and confusing isn't it ;-)
You should upgrade the .Net framework on the server to .Net 3.5 SP1, but you're still going to be running ASP.Net 2.0