is .NET 100% backwards compactable?

[chronodekar]

My understanding was that a .NET 1.0 byte-code will run the same on a .NET 1.0, 2.0 or 4.0 framework without any difference.

Recently Microsoft announced that some .NET API related to Oracle would be depreciated from 4.0 onwards. That made me realize that the source-code might not be compatible across the different SDKs.

So, if we code for .NET 1.0 today, we might need to change our source code if we're trying to compile with the .NET 4.0 SDK.

Is my understanding correct?

-cd

PS - I'm in a hurry this morning to google it, so any follow-up links will be most appreciated.

 

[Snapster]

Some things get depreciated between versions (eg: System.Web.Mail to System.Net.Mail) and you will be warned by the compiler or such depreciations and will have to make changes at some point. As good as Microsoft is at maintaining legacy API's, you should always test after recompiling in a new version out of good practise, even if there are no warnings / errors picked up.

 

[chronodekar]

Originally posted by: Snapster
Some things get depreciated between versions (eg: System.Web.Mail to System.Net.Mail) and you will be warned by the compiler or such depreciations and will have to make changes at some point. As good as Microsoft is at maintaining legacy API's, you should always test after recompiling in a new version out of good practise, even if there are no warnings / errors picked up.

Good to hear that. Yes, after every compile, testing is a MUST. There can be no real substitute.

But for an old .NET byte-code that was compiled using .NET 1.0, if it used something that is depreciated now, will it still run in the .NET 3.5 framework?

I'm not asking about re-compiling, just using the same executable.

-cd

 

[avnair2]

My undestanding of .NET is that you will have to install the 1.0 framework. You can have (and probably do) multiple versions of the .NET framework installed on a computer at any given time, and it will automatically select at runtime the 1.0 .dlls to load with your compiled application. So, as long as Microsoft supports the .NET 1.0 framework on the OS you are trying to run it on you should be OK. I have no idea what versions of .NET they are going to support on Windows 7 for instance.

 

[Snapster]

Originally posted by: chronodekar
Good to hear that. Yes, after every compile, testing is a MUST. There can be no real substitute.

But for an old .NET byte-code that was compiled using .NET 1.0, if it used something that is depreciated now, will it still run in the .NET 3.5 framework?

I'm not asking about re-compiling, just using the same executable.

-cd

If you have the version of the framework installed that the application was targeted for then that version will be used (side by side compatibility). If you however, do not have the target version installed for example .Net 1.1 in Vista is not installed by default the next newer version will be used and 'should' run as expected (2.0 in this case even if you had 3.x installed).

As previously mentioned there are some parts of the framework that were depreciated due to security changes.

 

[chronodekar]

Hmm... that's kinda disappointing. So my original assumption was wrong. It's better to have the framework that my code was targeted for.

Thanks a lot for your help guys! :thumbsup:

-cd

 

[imported_Dhaval00]

Refer to this: http://blogs.msdn.com/astebner...009/04/20/9557946.aspx

 

[chronodekar]

Originally posted by: Dhaval00
Refer to this: http://blogs.msdn.com/astebner...009/04/20/9557946.aspx

Almost forgot, thanks!!

-cd