Order an object from array order

Question

I am trying to order a JSON object, by using an integer value which is nested in it. the approach I have taken is to order the incoming data as readably as possible. Which I create a new JSON object with:

var newDataFormat = {"route": route, "destination": destination, "countdown": countdown};

busJSON.push(newDataFormat);

Then I create an array to act as the ordering mechanism. Which takes the 'countdown' integer, and then sorts by that number:

for (var i = totalStops - 1; i >= 0; i--) {

    countdownArray.push(parseInt(busJSON[i].countdown));

}

countdownArray.sort(function(a,b){return a - b});

Once I have these, I have one last loop, to push the information to the browser:

for (var i = dataMin; i < dataMax; i++) {

    if (countdownArray[i] === i) {

        items.push("<tr><td>" + busJSON[i].route + "</td><td>" + busJSON[i].destination + "</td><td>" + busJSON[i].countdown + "</td></tr>");

    }

}

The problem seems that it doesn't quite push all of the items to the browser, which I have made a demo of here:

http://tfl.applied-espi.com/bus-popup/

Is there a more correct/efficient way I should be doing this?

Technically object properties don't have an order (at least in ECMAScript). Anyways, you need to maintain the key association, which it looks like you're losing when pushing countdown... http://stackoverflow.com/questions/3824392/javascript-natural-sort-array-object-and-maintain-index-association — zamnuts, Nov 26 '13 at 12:32

score 1 · Accepted Answer · answered Nov 26 '13 at 12:52

An array is also a valid json format, so you can have

var busJSON = [];

then you push some objects to it and want to order them by a member of the objects

busJSON.push({"route": route, "destination": destination, "countdown": countdown});

so you have now an array of objects, as we know an array can be sorted so we sort it by its countdown value

busJSON.sort(function(a,b){return a.countdown - b.countdown});

now we have the objects sorted in ascending order, so we do some action for each element in the array

busJSON.forEach(function(value) {
    items.push("<tr><td>" + value.route + 
              "</td><td>" + value.destination +
              "</td><td>" + value.countdown + "</td></tr>");
});

voila!

Order an object from array order

1 Answers1