Sorting JSON items that meets certain criterias

Question

I'm trying to sort the JSON by release date, by random, by alphabetical order or by popularity. I'm not sure if the answer is on here, I checked and I can't seem to figure out if it's for me.

My JavaScript jQuery code grabs the JSON file for me:

$.getJSON("js/example.json", function(data) {
    $.each(data.articles, function() {
        //code
    });
});

I want JavaScript to collect the data from all the items in the articles and sort them. After that, it could probably be added into the HTML through a for() or something better.

Here is what the JSON looks like.

{
    "articles":[
        {
            "name":"aaa",
            "date":"10/13/15",
            "views":65
        },
        {
            "name":"ccc",
            "date":"10/17/15",
            "views":175
        },
        {
            "name":"bbb",
            "date":"10/11/15",
            "views":54
        },
        {
            "name":"ddd",
            "date":"10/17/15",
            "views":6
        }
    ]
}

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort — charlietfl, Oct 14 '15 at 04:39
Possible duplicate of [Sorting JSON by values](http://stackoverflow.com/questions/881510/sorting-json-by-values) — Sarjan Desai, Oct 14 '15 at 04:45

Damon Kaswell · Answer 1 · 2015-10-14T05:00:36.110

0

JavaScript has an array sort: ~~http://www.w3schools.com/jsref/jsref_sort.asp~~

Never mind, it's been pointed out to me that this link doesn't have any pertinent examples. Nevertheless, I do think sort is what you're looking for.

edited Oct 14 '15 at 05:00

answered Oct 14 '15 at 04:40

Damon Kaswell

1,270
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It will not work for object..Link contains only `string` array – Sarjan Desai Oct 14 '15 at 04:41
@SarjanDesai Array sort works fine with objects like above. Are you concerned about the fact that it's associative? – Damon Kaswell Oct 14 '15 at 04:47
You know, you're right. I could have sworn that was the link I used when I was trying to figure out the same thing, but it isn't. Thanks for pointing it out. – Damon Kaswell Oct 14 '15 at 04:57

score 0 · Answer 2 · answered Oct 14 '15 at 04:56

Fiddle:

https://jsfiddle.net/ppLso0mg/

You can usually utilize the someArr.sort() function, which takes a comparator function. The function works by giving you a and b which you have to determine the order of.

Here is an example of 3 different comparators for 3 different properties on your JSON object. I'll let you use your imagination on how you could clump them together into one big function. But this should at least illustrate how it works.

var json = 
[
{
"name": "aaa",
"date": "10/13/15",
"views": 65
},
{
"name": "ccc",
"date": "10/17/15",
"views": 175
},
{
"name": "bbb",
"date": "10/11/15",
"views": 54
},
{
"name": "ddd",
"date": "10/17/15",
"views": 6
}
];

var sortFunctions =
{
    name: function(a, b)
    {
        return a.name.localeCompare(b.name);
    },
    date: function(a, b)
    {
        if(a.date == b.date)
        {
            return 0;
        }

        var aDate = new Date(a.date);
        var bDate = new Date(b.date);

        return aDate > bDate ? 1 : -1;
    },

    views: function(a, b)
    {
        if(a.views == b.views)
        {
            return 0;
        }

        return a.views > b.views ? 1 : -1;
    }
};

json.sort(sortFunctions.name);
console.log(json);

json.sort(sortFunctions.date);
console.log(json);

json.sort(sortFunctions.views);
console.log(json);

I think you'd need to do a little more _work_ with the date - date strings are a cross browser, international PITA — Jaromanda X, Oct 14 '15 at 04:59
Definitely. This is but a brief demonstration. There are libraries for that. ;) — flagoworld, Oct 15 '15 at 16:36

score 0 · Answer 3 · answered Oct 14 '15 at 05:12

You can actually specify your own comparation function for the sort method of the array. The comparator function should receive 2 parameters and return:

-1, if the first parameter should go before the second in the sorted array.
0, if you consider both parameters to be equal (either one can go before).
1, if the first parameter should go after the second parameter.

Using that, you can create your own, ad hoc comparator function and sort the array using your own criterion. As an example, you can see here a function for sorting your array based on its name property and another one for sorting based on its views property:

function compareByName(a, b) {
    var namea = a.name, nameb = b.name;
    for(var i = 0; i < namea.length && i < nameb.length; i++) {
        if(namea.charCodeAt(i) !== nameb.charCodeAt(i))
            return namea.charCodeAt(i) - nameb.charCodeAt(i);
    }
    return namea.length - nameb.length;
}

function compareByViews(a, b) {
    return a.views - b.views;
}

With those functions created and with your object containing the articles stored in data, you can sort it like this:

data.articles.sort(compareByName); //sort by name
data.articles.sort(compareByViews); //sort by views

You can see a full example working here.

Sorting JSON items that meets certain criterias

3 Answers3