Check value in JSON object

Question

I need to find out if id exists in my JSON object, for example:

{ "requested": "2009-07-25T14:12:25+01:00", "channels": [ {"id": 1, "name": "General", "created": "2009-07-25 14:00:02"} ] } 

In particular, I need to check if my id (say 2) is in the channels. i .id . How can I do that?

Answer 1

Try the following:

 var id = 2, found = false; for (var i=0; i<channels.length; i++) { if (channels[i].id == id) { found = true; break; } } 

Answer 2

Or more briefly and probably faster:

 var id = 2; for (var found, i = channels.length; i && !(found = channels[--i].id === id);) ;