Why a css attribute defined using a class in css is not acessible via style property in javascript?
for example html
<div id="greendiv" class="green"></div>
css
.green {
background-color: green;
}
javascript:
var divcolor = document.getElmentById("greendiv").style.backgroundColor;
Problem: divcolor does not get 'green', backgroundColor has no value;
the same is true for 'getAttribute()';
Modificado por cor-el a
Todas as respostas (4)
That only works if you define the background-color via a style attribute and not via a style sheet.
<div id="greendiv" style="background-color: green;"></div>
var divcolor = document.getElementById("greendiv").style.backgroundColor;
Otherwise you need to use getComputedStyle
N=document.getElementById("greendiv");
window.getComputedStyle(N,'').getPropertyValue("background-color");
document.defaultView.getComputedStyle(N,'').getPropertyValue("background-color");
https://developer.mozilla.org/en-US/docs/Web/API/Window/getComputedStyle https://developer.mozilla.org/en-US/docs/Web/API/Document/defaultView
That is annoying a simple change in design and the code is broken...
There ain't a way to reach the data no matter how I set up?
The web is really disgusting all those silly and incompatible standards that just bloat up memory and cause no ease ...
Hi alfgaar, this is very old behavior, and you're not the first person to find it clumsy/awkward to have to use getComputedStyle().
To give you an example, here's an article from April 2006 proposing an alternate function that can easily check both inline styles and other styles in one step:
https://robertnyman.com/2006/04/24/get-the-rendered-style-of-an-element/
You may find it more convenient to use a JavaScript library for this, or grab some of their code for your use. For example, using jQuery: