I'm working on a C# Code that has as Targeted Framework .NET 4.6, and I'm trying to troubleshoot some issues that occurs during the execution.
That code is running on some clients, that has a .NET 3.5 Version.
My question is, does .NET 4.6 supports retro-compatibility, and if so, should it be wiser to have an aligned Framework versions (Target Version same as Client Version)??
TL;DR: Basically, you can run old on new, but not new on old.
DotNet 4.6+ is backwards compatible in the sense, that you can run an App built with DotNet 3.5 etc. But you cannot run an app built with DotNet 4.6+ while using an older installed framework eg. 3.5 or others. Take it this way:
Imagine you have a windows 10 computer and you want to install an app built for windows 8 or even XP and older. Modern windows has the compatibility layers, necessary to run or install the program.
Now what you/your clients are doing is basically taking an app specifically designed for windows 10, and trying to run it on Windows XP or 95 etc. That won't work as the compatibility layers are not in place to support the "future". No one can foresee the new features and API's that they might add, so the app is incompatible with older Windows.
If you are targeting .NET 4.6, then target .NET 4.6.
Do not expect your code/app to be compatible with anything lower, and if you do need it to be, you have to target that specific version. Which has its own draw-backs as the newer methods / ways of doing things and many libraries you could be using do not apply/are not compatible.
You can either update everything to use 4.6 or higher, or switch your codebase to target 3.5 and live with the drawbacks.
From Backward Compatibility
The .NET Framework 4.5 and later versions are backward-compatible with
apps that were built with earlier versions of the .NET Framework. In
other words, apps and components built with previous versions will
work without modification on the .NET Framework 4.5 and later
versions.
In your case app is built on .Net Framework 4.6 and the platform on client machine is 3.5 version. There might be some issues because app requires newer version than platform it runs.
.NET Framework version 4.6 was included with Windows 10 from version 1507 and .NET Framework version 4.6.2 was included with Windows Server 2016. If your clients are running either of these versions of Windows or newer, you won't have to install anything to run your .NET Framework 4.6 app, and it won't be running on .NET Framework 3.5 even if you do have it installed.
If you're using an older version of Windows than that and don't have .NET Framework 4.6 or newer installed, I wouldn't expect it to run at all.
Related
If I update from .net 4.5 to .net 4.8 when i compile my project. Does that introduce a risk that the clients cant run the dlls?
Do all users have to upgrade to .net 4.8 on their machines or are the .net version backwards compatible? They have all been able to run the app when it was compiled with .net 4.5.
What im trying to ask is if i risk that some clients wont be able to run the app by upgrading the Target Framework when building it.
This is from 4.5 to 4.8.
Does that introduce a risk that the clients cant run the dlls?
Yes
Do all users have to upgrade to .net 4.8 on their machines
Yes, if they do not already have it.
are the .net version backwards compatible?
Yes, they are backwards compatible, meaning a user with .net 4.8 can run programs written for .net 4.5 with no issue. Not the other way around.
What i'm trying to ask is if i risk that some clients wont be able to run the app by upgrading the Target Framework when building it.
They should have .net 4.8 installed since it is bundled with windows 10 1903 and later. See versions and dependencies. All older versions of windows 10 is end of life. The only exceptions are windows server 2019/2016.
Even if your client lacks .Net 4.8, windows should simply ask if they want to install .net 4.8, so it should be very easy to do as long as the users have permission to install things on their computers.
i am developing WPF application in visual studio and using .NET 3.5.
does the application fits Windows7 and Windows8 OS with no .NET framework additional installation?
do i need to add .NET 3.5 installation to setup project?
In Windows 7 .NET framework 3.5 is part of the operating system so all machines should have it.
In Windows 8 or windows 8.1 .NET framework 3.5 is NOT automatically installed (though all machines that are upgraded from win 7 -> win 8 should have it).
To run apps that require the .NET Framework 3.5 on Windows 8 or later, you must enable version 3.5 on your computer. There are two ways you can do this: by installing or running an app that requires the .NET Framework 3.5 (that is, by installing the .NET Framework 3.5 on demand), or by enabling the .NET Framework 3.5 in Control Panel. Both options require an Internet connection.
If an app requires the .NET Framework 3.5, but doesn't find that version enabled on your computer, it displays a message box, either during installation, or when you run the app for the first time. In the message box, choose Install this feature to enable the .NET Framework 3.5.
The above require an internet connection. If this is not possible you will have to include the .exe files of .NET 3.5 in your distribution
however as MSDN states:
The .NET Framework 4.5 and its point releases are backward-compatible
with apps that were built with earlier versions of the .NET Framework.
In other words, apps and components built with previous versions will
work without modification on the .NET Framework 4.5. However, by
default, apps run on the version of the common language runtime for
which they were developed, so you may have to provide a configuration
file to enable your app to run on the .NET Framework 4.5
So build your project for 3.5 and just deploy it to windows 8 machines. It should run, but its not the "best" environment for the app. The "best" would be to have .NET 3.5 installed.
If the user's PC has only Framework 2.0 installed, will Framework 4.0 work?
I installed windows 7 on my other laptop and tried to run my application built on C#, it didn't work. I figured out that my application is targeted for Framework 4.
When I ran this app on that laptop, it didn't work.. I wonder why, i thought that framework is already installed with windows. It's either it has an old Framework version ( like 2.0 ) OR it doesn't have any Framework installed.
Should I change my target to Framework 2.0 in order to make it work?
If the user's PC has only Framework 2.0 installed, will Framework 4.0 work?
If the user has only .NET 2.0 installed and you attempt to run an application compiled against .NET 4.0 it won't work.
On the other hand if the user has .NET 4.0 installed and you attempt to run an application compiled against .NET 2.0 this will work.
I am not aware of any forward compatible frameworks. Only backwards compatible. Makes sense?
Should I change my target to Framework 2.0 in order to make it work?
Yes, if you want to run your application on a computer that has only .NET 2.0 installed.
I'm writing a C# app (in VS 2008). If I target the .Net 3.5 framework, will it run on Windows XP and above? Will XP users potentially have to download a .Net upgrade?
UPDATE
If the app is intended for business / corporate environments do you think it's pretty safe to target 3.5 rather than 2.0?
Only Windows 7 and newer will come with .NET 3.5 (SP1) pre-installed; Windows XP and Vista users, while able to run apps built on .NET 3.5, have to download and install it first in order to use your app.
I think the latest service packs of XP and Vista include .NET 3.5, though.
If the app is intended for business / corporate environments do you think it's pretty safe to target 3.5 rather than 2.0?
Not if the client machines are not able to upgrade or install the 3.5 Framework.
It's not safe to assume they already have the framework. It is realistic, however, to have them install the framework. They probably have it, and if they don't then they should get it if you're writing an app in 3.5.
Hello friends i need an explanation regarding .NET framework pre-requisite while installing the published application in the target machine.
As java is downward compatible, by which i mean that if i have installed java v1.6 and if the application is developed using java v1.5 (i also mean that only classes and packages available in 1.5 are used to build the appln.)
I am sure that the application developed will definitely run by installing the latest or higher versions of jre or j2se.
Similarly in the case of .NET platform suppose if i develop my application using .NET framework 3.5 and in the target machine i have installed .NET framework 4.0 (the latest) even then it prompts to install the .NET framework 3.5 why is this so?
The real time example is i have downloaded and tried installing MySQL workbench and also installed .NET framework 4.0 But it still asks to install the .NET framework 3.5 before running the MySQL installation.
My question is does .NET framework is downward compatible as java or .NET?
Version Compatibility in the .NET Framework:
The .NET Framework 4 is
backward-compatible with applications
that were built with the .NET
Framework versions 1.1, 2.0, 3.0, and
3.5. In other words, applications and components built with previous
versions of the .NET Framework will
work on the .NET Framework 4.
However, in practice, this
compatibility can be broken by
seemingly inconsequential changes in
the .NET Framework and changes in
programming techniques. For example,
performance improvements in the .NET
Framework 4 can expose a race
condition that did not occur on
earlier versions. Similarly, using a
hard-coded path to .NET Framework
assemblies, performing an equality
comparison with a particular version
of the .NET Framework, and getting the
value of a private field by using
reflection are not backward-compatible
practices. In addition, each version
of the .NET Framework includes bug
fixes and security-related changes
that can affect the compatibility of
some applications and components.
If your application or component does
not work as expected on the .NET
Framework 4, use the following
checklists.
For .NET Framework 2.0, 3.0, and 3.5 applications:
Check .NET Framework 4 Migration
Issues for any changes that might
affect your application and apply the
workaround described.
If you are recompiling existing source
code to run on the .NET Framework 4,
or if you are developing a new version
of an application or component that
targets .NET Framework 4 from an
existing source code base, check
What's Obsolete in the .NET Framework
for obsolete types and members, and
apply the workaround described.
(Previously compiled code will
continue to run against types and
members that have been marked as
obsolete.)
If you determine that a change in the
.NET Framework 4 has broken your
application, check the Runtime
Settings Schema to determine whether
you can use a runtime setting in your
application configuration file to
restore the previous behavior.
If you encounter an issue that is not
documented, file a Microsoft Connect
bug and contact netfxcf#microsoft.com
with the bug number.
Yes, .Net 4 framework is backwards compatible with applications built on previous versions of .Net. You can see this link on MSDN for more info.
If you have .Net 3.5 or .Net 4 installed and a third party still requires either (or and older version) then the installer is not checking the correct prerequisite install conditions.