We have a large & complex system running under .Net 4.0. We want to start introducing code written for .Net 4.5, but can't (yet) assume that .Net 4.5 is installed on all the developer machines, build machines and test labs. So I'm looking for a way to compile certain projects in MSBuild using assemblies which are available on disk, on machines which have only .Net 4.0 installed.
Per the documentation it seems possible. The 4.5 reference assemblies are available in the msbuild environment, and I've been experimenting with the TargetFrameworkVersion, FrameworkPathOverride and TargetFrameworkMoniker attributes, but so far without success.
Any hints, suggestions or working samples would be most helpful.
To build a .NET Framework 4.5 application, you must also have the .NET Framework 4.5 reference assemblies.
Installation
The .NET Framework 4.5 replaces the common language runtime (CLR), targets, tasks, and tools of the .NET Framework 4 without renaming them. Essentially, it creates a modified and improved .NET Framework 4.
Related
I'm trying to create portable F# library but it needs to target .NET 4.0 (company policy is that all portable libraries need to be compatible with Windows XP).
When I create (Visual Studio 2013) new project there is an option "Portable Library (Legacy)" with description saying "A project for creating an F# library (.dll) that can run on .NET Framework 4.0 and higher, Windows Store and Silverlight 5".
The problem is, when the project is actually created. When I go to project's properties "Target Framework" is set to ".NET Portable Subset (.NET Framework 4.5, Silverlight 5, Windows 8)".
I tried changing F# runtime version from 3.1 to 3.0 but it does not change anything. "3.0" and "3.1" are the only options. What happened to "2.0"?
Am I missing something?
EDIT: It seems like Grzegorz is right. I've created this F# PCL which is saying ".NET 4.5" and referenced it from .NET 4.0 C# application. No problems were reported.
Then, to be sure, I also referenced it from 3.5 application and... no problems were reported during compilation either, but it was crashing on runtime. So to be sure, I ran the "potentially 4.0" application on XP and it worked, which may be interpreted as: "Yes, F# PCL does not depend on 4.5 even it it says so".
Make it an answer so I can tick it.
The template file for "Portable Library (Legacy)" has TargetFrameworkVersion hardcoded as v4.0. If You'll create a project with this template it'll in fact target 4.0 version.
Probably, there's a bug in UI that keeps displaying target framework as 4.5 while in reality it uses previous one.
To be strict, the issue is related to legacy Portable Library. The non-legacy version seems to work correctly in forcing framework to be in 4.5 version.
update:
I submitted an issue about this to Visual F# Tools team:
https://visualfsharp.codeplex.com/workitem/95
According to MSDN documentation,
public static Assembly LoadFrom(string assemblyFile)
throws BadImageFormatException if
assemblyFile is not a valid assembly.
-or-
Version 2.0 or later of the common language runtime is currently loaded
and assemblyFile was compiled with a later version.
Actually, there is one extra case - loading assembly that is built for x86 from assembly that runs in x64 mode. Maybe it is included in "not a valid assembly" statement, I don't know. But this is reasonable cause of exception.
Ok, but in .NET 4.5 it doesn't! I have a .NET 4.5 WPF app, that loads different appliations for some reason. It is building for Any CPU and I'm starting it on x64 Win 7. I've been testing it on one executable, that is built for .NET 4.0 x86, and it worked fine. But when I switched my app to .NET 4.0 it began to crash on Assembly.Load method!
So, my question is, am I missing something? If not, then how did they do that - loading x86 assembly from x64 process in .NET 4.5? I'm lacking some understanding at this point.
Update
Thanks to Hans Passant, I've figured out my mistake. Actually the behavior of Assembly.Load is no different. It turned out, I didn't notice Prefer 32-bit option in project settings (or Prefer32Bit tag in .csproj file). That's why my process in .NET 4.5 ran in a 32-bit mode. This setting was true when I created WPF .NET 4.5 project. Then, when I swithced to .NET 4.0 it became inactive because there was no such an option in .NET 4.0. And when I switched back to .NET 4.5 it became false, which is so, I guess, for compatibility purpose.
Let's clear one assumption off the table quickly, there is no possible way to have different behavior on a machine that has .NET 4.5 installed. Targeting 4.0 makes no difference at runtime. The only thing that does is select a different set of reference assemblies, they prevent you from accidentally using a class that's available on .NET 4.5 but not on .NET 4.0.
There is no way to have both 4.0 and 4.5 installed on the same machine. .NET 4.5 is not a side-by-side version of the .NET framework, like 3.5 and 4.0 are side-by-side. Installing 4.5 replaces an installed 4.0 version. The CLR, the jitter, all the runtime assemblies plus the C# compiler.
It is best here to focus on the Platform target setting of your EXE project, that's the one that selects the bitness of the process. The kind of mistakes you can make is forgetting that the setting can be different for the Debug vs the Release build. And assuming that the "Active solution platform" combobox in Build + Configuration Manager has any effect. It doesn't, only the Project + Properties, Build tab, Platform target setting matters. This is a very awkward trap that many programmers have fallen into.
I have developed a Windows application in the 4.0 framework. After deploying my application I have tried to install it in a Windows XP SP2 system, but when I try it I get some kind of requirement error. So I decided to change my application from 4.0 to the 2.0 framework so that it can be installed in any windows OS. Before that I tried with 3.5 and 3.0 but the framework's setup size exceeded 200mb, so I chose 2.0 because it already comes along with windows xp or later. The problem I am having is while changing my framework from 4.0 to 2.0 i'm getting reference problems with system.core and system.linq so now I cant build my project. What needs to be done to fix these reference errors?
The problem is that System.Linq, for example, didn't exist in .NET 2. If you are using anything that required System.Linq methods (such as LINQ or any extension methods), you'll have to rewrite that portion of your code to use .NET 2 only options.
Personally, I would just target .NET 3.5sp1 or .NET 4, and include the web installer, as this is a small addition to your deployment (the 4.0 web installer is under 1mb - many installers include a way to just package this instead of the full framework). Most systems already have .NET 3.5sp1 (and many have 4.0), so the effort to include this in your deployment is typically far smaller than trying to rework your application to avoid it.
Background
We have a C++ solution that has been moved from VS2005 to VS2010 where the project files were targeting the .net framework 3.5 but since moving over to VS2010, all of the project files were showing that they were targeting the.net framework 4.0. I have since changed the .vcxproj files manually so that they are targeting the .net framework 3.5, using the method described in the Community Content on this link
The Problem
When I build these project files, manually or via an automated build, the output assemblies are still targeting the .net framework 4.0. I can tell this by using various methods described here. I also know that this is the case as I build and run the installer for this application. Once the application has been installed (which then shows as a service), I try to start the service on the target machine. This service will not start on a machine without the .net framework 4.0 installed. If 4.0 is then installed, the service will start, so this is another test that I can run that shows me that the application has a dependency on .net framework 4.0 which it should not.
The Aim
Ideally, I need to build this application so that the outputs are targeting the .net framework 3.5 instead of 4.0 so that it will actually run as it is supposed to! I have tried to use the 3.5 version of MSBuild as described in one of the answers given for this question here but got the same error that is described underneath that post.
Can anyone help with this? It's proving to be a right pain and I've been banging my head against the wall for over a week trying to get this sorted!
Thanks again in advance
Make sure you follow all the instructions as provided in the first link you posted.
For example,
Make sure you have Visual Studio 2008 installed on the build server.
Make sure you also change each project's "Platform Toolset" to v90.
Verify the project's framework version: "In Solution Explorer, right-click your project and then click Properties. In the Property Pages window, in the left pane, expand Common Properties and then select Framework and References. Verify that the new Framework version appears at the top of the right pane."
Can anyone tell me why when I create Monotouch projects in the latest drop of MonoDevelop it is targeting the 1.0 framework instead of 3.5, as my projects in earlier versions do? This causes it to not be loadable in VS2010, which I tend to use for coding, while building/testing in MonoDevelop. Here is the version info:
Release ID: 20509002
Git revision: 35a0397615c02f7830d46dfcd31a6c0cb86e9f85
Build date: 2011-04-06 03:37:58+0000
And here is the difference in the csproj files between versions:
Old:
<TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
New:
<TargetFrameworkVersion>v1.0</TargetFrameworkVersion>
The v3.5 was a bug; MonoTouch projects never targeted the .NET v3.5 framework. They target the MonoTouch framework, which is arbitrarily versioned as v1.0.
Improvements in MD 2.6 have allowed us to deal with custom .NET frameworks in a similar way to VS 2010. This means that instead of storing the "closest" .NET framework then internally switching it to the correct framework after the project is loaded, we can directly handle particular project types using a particular custom framework.
If you want to load MT project in VS, you already have to make changes to the project - temporarily remove the project flavor GUID (though a trivial VS addin could make that unnecessary). This framework version fix means that you also have to change the target framework to one that VS has. For MonoTouch 4, rather than using .NET 3.5, I would recommend using either Silverlight 4 or .NET 4.
The best solution would be to set VS to actually use the MonoTouch framework, so you'd get accurate code completion and compilation. In VS 2010 that's now possible. Simply set the TargetFrameworkIdentifier of the project to "MonoTouch", then install the custom framework by copying all the MonoTouch framework assemblies to C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\MonoTouch\v1.0 and adding a FrameworkList.xml manifest in the RedistList subdirectory.
I've created a small open source project that enables you to build MonoTouch projects inside Visual Studio 2010. The readme for the project also explains how to get round the "v1.0" problem for the target framework version.
The project is available at https://github.com/follesoe/VSMonoTouch.
Since that's a Monotouch project, nobody expects it to work for Visual Studio or Windows.