jQuery: get each element's width and sum them up

Question

How can I get each element's width and sum them up?

For instance, here is the HTML:

<div id="container">
<div class="block-item" style="width:10px"></div>
<div class="block-item" style="width:50px"></div>
<div class="block-item" style="width:90px"></div>
<div>

I can think of looping through each element, but how do I sum the numbers up?

$('.block-item').each(function(index) {
    alert($(this).width());
});

I want to get the total number of 150 (10 + 50 + 90).

Thanks.

Scapula

Answer 1

Use parseInt(value, radix):

var totalWidth = 0;

$('.block-item').each(function(index) {
    totalWidth += parseInt($(this).width(), 10);
});

Here's an example fiddle.

Aixlachapelle

Probably want a += for the collector, yes? – Mammillate

@Alex Thank you, caught that dumb typo myself when I was creating the fiddle. – Aixlachapelle

10 is a radix. without it you could get unexpected results when parsing. this way you get base 10 result as opposed to octal. – Rhodian

If you have the option to use reduce() you could simplify this further by doing $('.block-item').get().reduce(function(width, el){ return width + $(el).width() }, 0) – Podophyllin

Answer 2

var w = GetWidths('.block-item');

function GetWidths(id) {
    var i = 0;

    $(id).each(function (index) {
        i += parseInt($(this).width(), 10);
    });

    return i;
}

Chuppah

Clean and elegant usage of variables and functions passed between each other. – Millenarian

Answer 3

for those people who have seen this thread recently: you can use jQuery map with ease:

var y = $('.block-item').map( function() {
    return $(this).width();
}).get()
.reduce((partialSum, a) => partialSum + a, 0);
console.log(y)

Phonology