JSON Array - Extract Data With Javascript

Question

I have a really simple Json array and I need to get back

the number of items within the array.
the list of entries in order of the id.

The array is as follows:

{"error":false,"error_msg":"","body":
{"records":[{"name":"Application","id":1},
            {"name":"Fees Paid","id":2},
            {"name":"Evidence Verification","id":3},
            {"name":"Details QA","id":4},
            {"name":"Grade Approval","id":5},
            {"name":"Welcome Pack","id":6}]
},
"validation_errors":[]}

possible duplicate of [deserialize from json to javascript object](http://stackoverflow.com/questions/6487167/deserialize-from-json-to-javascript-object) — , Oct 18 '13 at 14:33
`body.records.name.length -> I need a `foreach statement to list out the names in order of their ids. The array is returned into a function as data therefore `data.body.records.name` has also been tried — Sideshow, Oct 18 '13 at 14:33
You're going to need to just loop over (parsed json data).records and then do work with records[i].id and records.length — megawac, Oct 18 '13 at 14:36

score 3 · Accepted Answer · answered Oct 18 '13 at 14:36

Assuming you have JSON.parsed your string into a variable called jsonobj, the following statements get the data you want:

var len = jsonobj.body.records.length;
jsonobj.body.records.sort(function(a,b) {return a.id-b.id;});
// now iterate through jsonobj.body.records and they will be in ascending ID order

score 1 · Answer 2 · answered Oct 18 '13 at 14:39

Say you have your Object held in variable jObj, clone the Array/Objects so you preserve the originals, sort it as desired then return an Array which just holds the name properties.

jObj['body']['records']
    .map(function (e) {return {'id': e['id'], 'name': e['name']};}) // clone
    .sort(function (a, b) {return +a['id'] - +b['id'];})            // sort asc
    .map(function (e) {return e['name'];});                         // get names
/* [
    "Application", "Fees Paid",      "Evidence Verification",
    "Details QA",  "Grade Approval", "Welcome Pack"
] */

JSON Array - Extract Data With Javascript

2 Answers2