How to build an array from a jSon object

Question

I am trying to build 2 arrays from JSON arrays.

{
    "2015-03-24": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "150",
        "promo": "",
        "status": "available"
    },
    "2015-03-25": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "150",
        "promo": "",
        "status": "available"
    },
    "2015-03-26": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "150",
        "promo": "",
        "status": "available"
    },
    "2015-03-27": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "100",
        "promo": "",
        "status": "available"
    },
    "2015-03-28": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "100",
        "promo": "",
        "status": "available"
    },
    "2015-03-29": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "100",
        "promo": "",
        "status": "available"
    },


    "2015-04-10": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "",
        "promo": "",
        "status": "booked"
    },
    "2015-04-11": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "",
        "promo": "",
        "status": "booked"
    },

    "2015-05-01": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "",
        "promo": "",
        "status": "unavailable"
    },
    "2015-05-02": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "",
        "promo": "",
        "status": "unavailable"
    },
    "2015-05-03": {
        "bind": 0,
        "info": "",
        "notes": "",
        "price": "",
        "promo": "",
        "status": "unavailable"
    },


}

This is the jSon array, so I want to build 2 arrays.

1 array holding only keys (in this case the date) of those element where status=='booked' nOR status=='unavailable' and build it in jQuery array like this

var array = ['2015-03-19', '2015-03-20', '2015-03-21', '2015-03-22', '2015-03-23', '2015-03-24', '2015-03-25', '2015-03-26', '2015-04-07', '2015-04-08', '2015-04-09', '2015-04-10'];

Another is building another array with the dates of those days where status=='available' AND price > '100$'

var array2 = [ '2015-03-25', '2015-03-26', '2015-04-07', '2015-04-08'];

How can I achieve this on with jQuery?

possible duplicate of [Convert array to JSON](http://stackoverflow.com/questions/2295496/convert-array-to-json) — arkoak, Mar 19 '15 at 12:24
it was deleted by the owner, I presume because it was written in PHP, and not javascript. — Jeff Lambert, Mar 19 '15 at 13:02
yes, I removed, because I did it in PHP, what a shame, I must try to do it in jQuery if there is still time... — n-dru, Mar 19 '15 at 13:07

n-dru · Accepted Answer · 2015-03-19T13:19:27.557

If j is your json:

var a1 = [];
var a2 = [];
$.each( j, function( key, ob ) {
    if(ob.price > 100 && ob.status == 'available'){
        a1.push(key);
    }
    if(ob.status == 'booked' || ob.status == 'unavailable'){
        a2.push(key);
    }
});
console.log(a1);
console.log(a2);

Yields:

["2015-03-24", "2015-03-25", "2015-03-26"]
["2015-04-10", "2015-04-11", "2015-05-01", "2015-05-02", "2015-05-03"]

score 1 · Answer 2 · answered Mar 19 '15 at 14:10

You could have a more generic approach, that could be useful to adapt in other scenarios of yours, without dependencies from jQuery. A small function for data filtering:

function from(data) {
  var predicates = [];
  var results = [];

  function exec() {
    for (var k in data) {
      if (data.hasOwnProperty(k)) {
        for (var i = 0, l = predicates.length; i < l; i++) {
          if (predicates[i](data[k])) {
            results[i][k] = data[k]
          }
        }
      }
    }

    return results;
  }

  exec.get = function(predicate) {
    predicates.push(predicate);
    results.push({});
    return exec;
  }

  return exec;
}

Giving that, you can now write code like:

// predicates
function isNotAvailable(item) {
  return item.status === "unavailable" || item.status === "booked"
}

function isAvailableAndPriceGreater100(item) {
  return item.status === "available" && +item.price > 100
}

// results
var results = from(obj)
               .get(isNotAvailable)
               .get(isAvailableAndPriceGreater100)
               ();

Where obj is your object with all the data.

That command will returns two array, one for each predicate defined, with all the object – because it could be useful if you want to access to some properties, o filter again. If you want only the keys, at that point you can simply do:

var notAvailableDates = Object.keys(results[0]);

score 0 · Answer 3 · answered Mar 19 '15 at 13:21

Try this,

var array1 = [];
var array2 = [];
$.each(data.items, function(key, val) {
   if((val.status == 'booked') || (val.status == 'unavailable')){
     array1.push(key);
   }
   if((val.status == 'available') && (val.price > 100)){
     array2.push(key);
   }
})

blablabla · Answer 4 · 2015-03-19T13:36:27.153

function obj_key_select(obj, func) {
    newArr = [];
    for(var index in obj) { 
        if (obj.hasOwnProperty(index)) {
            if(func(obj[index])) {
                newArr.push(index);
            }
        }
    }
    return newArr;
}

var dates = JSON.parse(jsonString);

var arrOne = obj_key_select(dates, function(element){
    return (element.status === 'booked' || element.status === 'unavailable'); 
});

var arrTwo = obj_key_select(dates, function(element){
    return (element.status === 'available' && parseInt(element.price) > 100); 
});

How to build an array from a jSon object

4 Answers4