如何在我的程序集中为app.config或硬编码配置值使用自定义名称

Question

I have written a class library in C# (mydll.dll) which accesses a third party dll (3rdpdll.dll). Mydll.dll, in turn gets consumed via COM interop by a non-.NET process (myapp.exe).

Mydll.dll is .NET 4.0 but 3rdpdll.dll has been built using v2.0.50727, so when I run myapp.exe, I get the following error:

Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information...

This gets fixed if I create a file called "myapp.exe.config" next to myapp.exe containing the following XML:

<?xml version="1.0"?>
<configuration>
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>
  </startup>
</configuration>

Problem is myapp.exe gets updated a lot and contains version information in the name, such as myapp.v2.063.exe. This would require the config file to be renamed with every new iteration of the app (myapp.v2.063.exe.config ).

Is there a way for me to declare a static name for the config file, such as "app.config" so that it does not need to be renamed and reshipped along with every new iteration of myapp.exe? Or better yet, could I hard-code the useLegacyV2RuntimeActivationPolicy attribute in mydll.dll so that I can avoid using a config file altogether?

Answer 1

In Visual Studio 2010 you can rename the app.config file with:

in Project -> Project Properties , select Build Events tab and edit the post-build event command-line to rename the .config file, example:

rename "$(TargetDir)$(TargetFileName).config" "$(TargetFileName).versionX"

Answer 2

I may be wrong but just thinking, if you recompile your .net 4.0 assembly in .net 2.0 framework, as .backward compatibility is there. Then i am thinking this error of mixedmode assembly should go and you may not need this config.

Answer 3

I went with Joe 's idea:

If MyApp.exe gets updated a lot, could you prevail on it to rename or even autogenerate the config file with a matching name before its first call into any .NET code? – Joe Jan 12 at 17:38