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javascriptarrays
Aistis
Aistis

Reputation: 241

Javascript: Getting the newest array

I've been thinking about how to display the newest array (because the array list would update from time to time.). I think there's a default function to it but I can't find it. Anyone knows it?

var bgImg = new Array();

bgImg[0] = "background.jpg";
bgImg[1] = "background2.jpg";
bgImg[2] = "background3.jpg";
bgImg[3] = "background4.jpg";

Upvotes: 0

Views: 58

Answers (2)

ChaosPandion
ChaosPandion

Reputation: 78272

You could create a little object to handle this for you.

function creatImageState() {
    var images = [];
    return {
        get latest() {                    
            return images[images.length - 1];
        },
        set latest (value) {
            images.push(value);
        }
    };
}

var s = creatImageState();

s.latest = "a.png";
s.latest = "b.png";

alert(s.latest);

IE doesn't support getters and setters so you probably need to use this.

function creatImageState() {
    var images = [];
    return {
        getLatest : function() {                    
            return images[images.length - 1]
        },
        setLatest : function(value) {
            images.push(value);
        }
    };
}

var s = creatImageState();

s.setLatest("a.png");
s.setLatest("b.png");

alert(s.getLatest());

Upvotes: 1

meder omuraliev
meder omuraliev

Reputation: 186572

If you want the last element of the array,

>>> a = ['background1','background2'];
["background1", "background2"]
>>> b = a[a.length-1]
"background2"

You shouldn't need to manually assign indexes. Just do bgImg.push('background2.jpg'), and it will mutate the array for you. In your case the syntax would be...

var last = bgImg[bgImg.length-1]

If you want the newest then you need to make a variable and set it with whatever you update when you push the newest one, if it doesn't become the last one.

Upvotes: 1

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