Get value of attribute in CSS - html

Question

I have this HTML code:
<div data-width="70"></div>
I want to set it's width in CSS equal to the value of data-width attribute, e.g. something like this:
div {
width: [data-width];
}
I saw this was done somewhere, but I can't remember it. Thanks.

Answer 1

You need the attr CSS function:
div {
width: attr(data-width);
}
The problem is that (as of 2021) it's not supported even by some of the major browsers (in my case Chrome):

Answer 2

You cant pass data attribute value directly in to css without pseudo type content.
Rather you can do this way.. CHECK THIS FIDDLE
<div data-width="a"></div><br>
<div data-width="b"></div><br>
<div data-width="c"></div>
CSS
div[data-width="a"] {
background-color: gray;
height: 10px;
width:70px;
}
div[data-width="b"] {
background-color: gray;
height: 10px;
width:80px;
}
div[data-width="c"] {
background-color: gray;
height: 10px;
width:90px;
}

Answer 3

Inline CSS variables are almost as declarative as data attributes, and they are widely supported now, in contrast to the attr(). Check this out:
var elem = document.getElementById("demo");
var jsVar = elem.style.getPropertyValue("--my-var");
function next() {
jsVar = jsVar % 5 + 1; // loop 1..5
elem.style.setProperty("--my-var", jsVar);
}
.d1 {
width: calc( var(--my-var) * 100px );
background-color: orange;
}
.d2 {
column-count: var(--my-var);
}
<button onclick="next()">Increase var</button>
<div id="demo" style="--my-var: 2">
<div class="d1">CustomWidth</div>
<div class="d2">custom columns number custom columns number custom columns number custom columns number custom columns number custom columns number custom columns number</div>
</div>

Answer 4

Another approach would be using CSS Custom Properties with style element to pass values from HTML to CSS.
div {
width: var(--width);
height: var(--height);
background-color: var(--backgroundColor);
}
<div
style="
--width: 50px;
--height: 25px;
--backgroundColor: #ccc;
"
></div>
<div
style="
--width: 100px;
--height: 50px;
--backgroundColor: #aaa;
"
></div>

Answer 5

CSS is static styling information about specific html element and not the other way around. If you want to use CSS to set the width of your div I suggest you do with the use of classes:
HTML:
<div class="foo"></div>
CSS:
.foo {
width: 70px;
}
jsFiddle

Answer 6

I'm just having fun with this, but a jQuery solution would be something like this:
HTML
<div class='foo' data-width='70'></div>
<div class='foo' data-width='110'></div>
<div class='foo' data-width='300'></div>
<div class='foo' data-width='200'></div>
CSS
.foo {
background: red;
height: 20px;
margin-bottom: 10px;
width: 0; /** defaults to zero **/
}
jQuery
$(document).ready(function(){
$('.foo').each(function(i) {
var width = $(this).data('width');
$(this).width(width);
});
});
Codepen sketch here: http://cdpn.io/otdqB
KIND OF AN UPDATE
Not what you're looking for, since you want to pass a variable to the width property. You might as well use a class in this case.
HTML
<div data-width='70'>Blue</div>
CSS
div[data-width='70'] {
width: 70px;
}
Sketch here: http://cdpn.io/jKDcH

Answer 7

<div data-width="70"></div>
use `attr()` to get the value of attribute;
div {
width: attr(data-width);
}

Answer 8

can you try this
$(function(){
$( "div" ).data( "data-width" ).each(function(this) {
$(this).width($(this..data( "data-width" )))
});
});