Given a Facebook username, how do I get the ID of the profile?

I want the ID, not the 开发者_如何学Cusername. But given the username...what do I have to do?

https://graph.facebook.com/username

e.g.

https://graph.facebook.com/boxoft

{ "id": "1264933131", "name": "Box He", "first_name": "Box", "last_name": "He", "link": "http://www.facebook.com/boxoft", "username": "boxoft", "gender": "male", "locale": "en_US" }

You wont be able to get an exact match but will get some results. Via Graph Api docs

https://graph.facebook.com/search?q=Owalla&type=user