Try like below (this is an example):
var json = {"forum":[{"id":"1","created":"2010-03-19 ","updated":"2010-03-19 ","user_id":"1","vanity":"gamers","displayname":"gamers","private":"0","description":"All things gaming","count_followers":"62","count_members":"0","count_messages":"5","count_badges":"0","top_badges":"","category_id":"5","logo":"gamers.jpeg","theme_id":"1"}]};
var forum = json.forum;
for (var i = 0; i < forum.length; i++) {
var object = forum[i];
for (property in object) {
var value = object[property];
alert(property + "=" + value);
}
}
Jquery way
$.each(json.forum, function(i, object) {
$.each(object, function(property, value) {
alert(property + "=" + value);
});
});
Check below mentioned link for more info :
jquery parse json multidimensional array
Another useful one :
help with jagged arrays