When adding an existing item with "Add as Link", this file is not compiled in VS2015?

Question

When adding an existing item with "Add as Link", this file is not compiled in VS2015 ?

Answer 1

Indeed, this is not yet supported. I contacted the engineering owners of this feature and they are investigating what it would take to support this.

You can manually add a "linked" file in the project.json file:

{
    ... other stuff ...

    "compile": [
        "../path/to/somewhere.cs",
        "../../another/path/to/file.cs",
        "../../use/globbing/**/*.cs"
    ],

    ... other stuff ...
}

The schema for the file is available here: https://github.com/SchemaStore/schemastore/blob/master/src/schemas/json/project.json#L98-L119

And in Visual Studio while editing a project.json file you'll see this same schema in Intellisense.