dot net core build platform/os specific code or class files

Question

I want to build a .net core library that will have platform specific code for doing win32 and osx calls and when compiling the library for each target os, I want to include

Answer 1

You could define a build definition in your project.json

"buildOptions": {
                "define": [ "PORTABLE328" ]
            }

eg:

{
    "frameworks":{
        "netstandard1.6":{
           "dependencies":{
                "NETStandard.Library":"1.6.0",
            }
        },
        ".NETPortable,Version=v4.0,Profile=Profile328":{
            "buildOptions": {
                "define": [ "PORTABLE328" ]
            },
            "frameworkAssemblies":{
                "mscorlib":"",
                "System":"",
                "System.Core":"",
                "System.Net"
            }
        }
    }
}

Now you can conditionally compile against that target:

#if !PORTABLE328
using System.Net.Http;
using System.Threading.Tasks;
// Potentially other namespaces which aren't compatible with Profile 328
#endif

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