This kind of stuff exists in Eclipse:

But I\'ve not found it in Visual Studio yet. Is ther
This question was asked quite a while ago and before Visual Studio Code existed but I found it when searching for how to do this with Visual Studio Code so I thought others might stumble on this question too so I thought I'd share my solution. Here's how to do it in Visual Studio Code. I'm using TypeScript but it works for JavaScript, too.
1) View -> Open View
2) select (or type) Outline
3) You'll now get an Outline palette that shows full information on the class including properties and functions.