Platform target x86 and x64 at the same time in Visual Studio 2012

Question

I know how to change the Platform target of my C# project from here: http://msdn.microsoft.com/en-us/library/ms185328.aspx But my question is: Is it possible to target platforms x86 and x64 at the same time in visual studio 2012, so i will have two folders in my Debug directory like this:

Bin\Debug\x86(x86 dlls & exe)

Bin\Debug\x64(x64 dlls & exe)

So i always have the two platforms assemblies available on every build of my project.

EDIT: using Any CPU: When build my application using "Any CPU" platform and run it on a 64-bit operating system, the process has the extension 32* in Task Manager which means that it is a 32-bit assembly not 64-bit

Answer 1

I tried to build my application using "Any CPU" and when i run it on x64 windows, i found that the process in Task Manager has the extension 32*

You are being confuzzled by the solution configuration name. It defaults to "AnyCPU" for managed projects in VS2012 and up. Which is a fairly accurate name, a .NET project can run on any CPU thanks to the jitter. These configuration names are however only relevant to native projects (C and C++), they pick the kind of compiler that is used to build the project. Since they get built straight to machine code, a different compiler is needed to generate x64 code.

You can select the kind of jitter that's used at runtime, a modern version of Windows is able to run both 32-bit and 64-bit processes. But that's an entirely different setting, it doesn't have anything to do with the configuration name.

Right-click your EXE project, Properties, Build tab. Ensure that the Platform target setting is AnyCPU, untick the "Prefer 32-bit" checkbox if you see it. That removes the jitter choice forcing, your process will now be a 64-bit process on a 64-bit version of Windows. And still run on a 32-bit version, thanks to the jitter. Repeat this setting change for the Release configuration.

Do beware that you'll have to test this, there are various subtleties involved, related to the file system and the registry views that are different depending on the bitness. Having to test both flavors is the one of the reasons why .NET projects default to 32-bit mode.