Question

I’ve got a simple jQuery $("span.value") which select nodes containing text. This text is guaranteed to be an integer. How do I calculate the sum of all selected node’s text, and place the sum into another node?

<span class="value">3</span>
<span class="value">4</span>
<span class="value">5</span>
<span class="sum">?</span>

Answer 1

You could do this:

var sum = 0;    
$('.value').each(function(index, el) {
    sum += parseInt($(this).text());
});
$('.sum').text(sum); //careful - will set the text for *all* elements with class = sum

I’d suggest using an id instead of a class for the sum <span>, even if you’re sure there’s going to be just one. IMO, it’s be less error-prone..