Question

Ok, a little new to JSON format..

I have the following JSON string returned from an AJAX call, which firebug actually displays in a tree quite nicely.. however I can’t seem to be able to work out how to loop through the content…

{"data":{"item":[{"@id":"7","fromMemberID":"7","FromMember":"david","notificationsType":"event","notificationsDesc":"A new event (Test Event Thursday, 16 September 2010) has been created.","notificationsDate":"16 Sep 2010","notificationsTime":"00:02:18"},{"@id":"8","fromMemberID":"7","FromMember":"david","notificationsType":"event","notificationsDesc":"A new event (Test Event Thursday, 16 September 2010) has been created.","notificationsDate":"16 Sep 2010","notificationsTime":"08:26:24"}]}}

I have tried to say get a count of items.. alert(data.item.length);
or a loop:

for(i=0; i<data.item.length; i++)
{
    alert(data.item[i].FromMember);
}

obviously missing something fundemental…

Any ideas??

Answer 1

You were very close… “data” is actually a key in your JSON, so you have to refer to your JSON variable to access “data”…. so you want JSON.data.item[i].FromMember

Here is some full working code:

(function () {
    var json = {"data":{"item":[{"@id":"7","fromMemberID":"7","FromMember":"david","notificationsType":"event","notificationsDesc":"A new event (Test Event Thursday, 16 September 2010) has been created.","notificationsDate":"16 Sep 2010","notificationsTime":"00:02:18"},{"@id":"8","fromMemberID":"7","FromMember":"david","notificationsType":"event","notificationsDesc":"A new event (Test Event Thursday, 16 September 2010) has been created.","notificationsDate":"16 Sep 2010","notificationsTime":"08:26:24"}]}};

    var i;
    var iLength = json.data.item.length;
    for (i = 0; i < iLength; i++) {
        alert(json.data.item[i].FromMember);
    }
})();​

jsFiddle