我已经是基于.NET 2运行时的应用程序。我想补充的.NET 4的支持，一点点，但不想（在短期内），将整个应用程序（这是非常大的）目标.NET 4。

I've an application that is based on .NET 2 runtime. I want to add a little bit of support for .NET 4 but don't want to (in the short term), convert the whole application (which is very large) to target .NET 4.

我试图创建一个应用程序config文件的明显的方法，有这样的：

I tried the 'obvious' approach of creating an application .config file, having this:

<startup useLegacyV2RuntimeActivationPolicy="true">
  <supportedRuntime version="v4.0" />
</startup>

但我遇到了一些问题，我注意到here.

我创建一个单独的应用程序域的概念。为了测试它，我创建了一个WinForm的项目目标。NET 2.然后，我创建一个类库针对.NET 4。在我的WinForm的项目，我增加了以下code：

I got the idea of creating a separate app domain. To test it, I created a WinForm project targeting .NET 2. I then created a class library targeting .NET 4. In my WinForm project, I added the following code:

        AppDomainSetup setup = new AppDomainSetup();
        setup.ApplicationBase = "path to .NET 4 assembly";
        setup.ConfigurationFile = System.Environment.CurrentDirectory + 
          "\\DotNet4AppDomain.exe.config";

        // Set up the Evidence
        Evidence baseEvidence = AppDomain.CurrentDomain.Evidence;
        Evidence evidence = new Evidence(baseEvidence);

        // Create the AppDomain      
        AppDomain dotNet4AppDomain = AppDomain.CreateDomain("DotNet4AppDomain", evidence, setup);
        try
        {
            Assembly doNet4Assembly = dotNet4AppDomain.Load(
               new AssemblyName("MyDotNet4Assembly, Version=1.0.0.0, Culture=neutral, PublicKeyToken=66f0dac1b575e793"));
            MessageBox.Show(doNet4Assembly.FullName);
        }
        finally
        {
            AppDomain.Unload(dotNet4AppDomain);
        }

我的DotNet4AppDomain.exe.config文件看起来是这样的：

My DotNet4AppDomain.exe.config file looks like this:

<startup useLegacyV2RuntimeActivationPolicy="true">
  <supportedRuntime version="v4.0" />
</startup>

不幸的是，这将引发的BadImageFormatException当执行dotNet4AppDomain.Load。难道我做错了什么在我的code，或者是什么，我要做的只是没有去上班？

Unfortunately, this throws the BadImageFormatException when dotNet4AppDomain.Load is executed. Am I doing something wrong in my code, or is what I'm trying to do just not going to work?

感谢您！

推荐答案

您瞄准2.0所以它是一个在内存中加载......他们你问它加载了一块4.0图像...它不能工作，你需要旋转的正确版本的新运行例如，如果你想这样做。

You target the 2.0 so it is the one loaded in memory... they you ask it to load a 4.0 image... it can't work you need to spin a new Runtime instance of the correct version if you want to do that.

要做到这一点的唯一方法可能是将举办第二CLR在你的过程就像在的是否有可能举办CLR在C程序？巫成为可能与.net 4.0。

The only way to do that may be to Host a second CLR inside your process like explained in Is it possible to host the CLR in a C program? witch became possible with .Net 4.0.