Send a variable from javascript to a C# Application

Before i start writing a service in C# to listen for input, i would like to know if its even possible since there's not allot on the internet about it.

I have a unity game where if you press the action key, a JavaScript runs, which should send a variable to a c# application to start a voice recording application. Then if it released, it should send one again to stop the the recording.

Is this possible? Or Better yet, is this even practical?