How do I show reference count in Visual Studio Code?

This feature is called CodeLens.

In Visual Studio find it in menu Options → Text Editor → All languages → CodeLens.

And in Visual Studio Code it is in menu File → Preferences → Settings → "editor.codeLens": true

Visual Studio Code version 1.28.2:

You need to add this to User Settings:

Menu File → Preferences → Settings:

"typescript.referencesCodeLens.enabled": true,

The menu structure ususally changes during years. So in VSCode v.1.43 please follow the next steps:

1. Click Gear icon and go to Settings

2. In the "Settings" window in the input field type "reference", click "User" tab, under "Extensions" click "Typescript" and find "Reference Code Lens" checkboxes for javascript/typescript.

Checking/unchecking checkboxes will automatically apply your changes.