What is the resolution for obtaining an authorisation_code via Javascript

[ns1]

What is the resolution for obtaining an authorisation_code via JavaScript for the BOX API?

The documentation (http://developers.box.com/oauth/) suggests using POSTMAN or curl. In this example, like the clientID is 123 and secret code is 456 and so on. So i am using below URL in browser to get authorization code:

https://wwww.box.com/api/oauth2/authorize?response_type=code&client_id=33232323&redirect_uri=https://0.0.0.0&state=authentication

let's say the response is 'xyz' as authorisation_code.