如何加载多个mscorlib.dll并分别调用它们的内部函数？

Question

This is for research purpose. I have .Net framework 2.0 installed, and I want to load mscorlib.dll 1.1 dynamically to execute its specific inner function.

When I wrote this code in C#:

   static void Main(string[] args)
    {
        Assembly assem = Assembly.LoadFrom("C:\\mscorlib_my_private_1.1.dll");
        System.Type type = assem.GetType("System.Console");
        Type[] typeArray =new Type[1];
        typeArray.SetValue(typeof(string),0);
        System.Reflection.MethodInfo info = type.GetMethod("WriteLine", typeArray);
        object[] param = new object[1];
        param[0] = assem.FullName;
        type.InvokeMember("WriteLine",
        System.Reflection.BindingFlags.InvokeMethod, System.Type.DefaultBinder,
        "", param);
    }

The output is "mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" Not the expected 1.1 version .

After Googling a lot, I know that mscorlib.dll is very special, but is it impossible?

Answer 1

This is not possible: mscorlib.dll depends on internals of the .NET runtime it was written for. These internals will probably have changed in later versions of the .NET runtime!

So even if you could somehow trick the .NET runtime into loading the wrong mscorlib.dll, you'd find that some methods work and others create all kinds of weird errors (behavioral changes, binding errors or access violations).

Answer 2

You can't load any version of mscorlib other than the one for the .NET framework version you are running. If you request another, you get the one that is already loaded. This is why mscorlib has strict backwards compatibility.

Answer 3

This strikes me as impossible. What you could maybe do, though, is compile a program against every version of the .NET framework you want to target, and then run each of those programs from your main app.

Answer 4

.NET 2.0 does not allow to add a reference of mscorlib.dll of version 1.1. So to load mscorlib of version 1.1 you can do one thing that you write a pre-build script to copy this DLL to your bin (Or target folder) and this way your code will be able to access both versions of mscorlib.dll. eg. Copy $(Location of mscorlib.dll)\\mscorlib.dll $(TargetDir) will copy this file to output location of your project.