slash 
Convert Windows backslash paths to slash paths:
foo\\bar➔foo/bar
Forward-slash paths can be used in Windows as long as they're not extended-length paths and don't contain any non-ascii characters.
This was created since the path methods in Node.js outputs \\ paths on Windows.
Install
$ npm install slash
Usage
const path = require('path');
const slash = require('slash');
const string = path.join('foo', 'bar');
// Unix => foo/bar
// Windows => foo\\bar
slash(string);
// Unix => foo/bar
// Windows => foo/bar
API
slash(path)
Type: string
Accepts a Windows backslash path and returns a path with forward slashes.
License
MIT © Sindre Sorhus