在T4模板中获取ASPNETCORE_ENVIRONMENT？

Question

Within a T4 Template, I'm having trouble getting the value for ASPNETCORE_ENVIRONMENT in my project, currently set to "Development".

string env = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");

This appears to run fine, but pulls back null.

Answer 1

In my understanding, T4 is always Design Time -> Developement Environment. Therefore I am not sure, what exactly you are trying to do.

The environment variable is set in Properties/launchSettings.json and will be loaded if you start your project via Visual Studio:

"environmentVariables": {
  "ASPNETCORE_ENVIRONMENT": "Development"
}

Of course, T4 doesn't load the Variables configured in launchSettings.json , since it is not the application itself. You could parse the file manualy, or set the environment variable yourself in Windows or probably in MSBuild .