Changing element style attribute dynamically using JavaScript

I hav a certain style sheet for a div. Now i want to modify one attribute of div dynamically using js.

How can i do it?

document.getElementById("xyz").style.padding-top = "10px";

Is this correct?

In addition to other answers, if you want to use the dash notition for style properties, you can also use:

document.getElementById("xyz").style["padding-top"] = "10px";

It's almost correct.

Since the - is a javascript operator, you can't really have that in property names. If you were setting, border or something single-worded like that instead, your code would work just fine.

However, the thing you need to remember for padding-top, and for any hyphenated attribute name, is that in javascript, you remove the hyphen, and make the next letter uppercase, so in your case that'd be paddingTop.

There are some other exceptions. JavaScript has some reserved words, so you can't set float like that, for instance. Instead, in some browsers you need to use cssFloat and in others styleFloat. It is for discrepancies like this that it is recommended that you use a framework such as jQuery, that handles browser incompatibilities for you...

There is also style.setProperty function:
https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/setProperty

document.getElementById("xyz").style.setProperty('padding-top', '10px');

// version with !important priority
document.getElementById("xyz").style.setProperty('padding-top', '10px', 'important');

I resolve similar problem with:

document.getElementById("xyz").style.padding = "10px 0 0 0";

Hope that helps.

Assuming you have HTML like this:

<div id='thediv'></div>

If you want to modify the style attribute of this div, you'd use

document.getElementById('thediv').style.[ATTRIBUTE] = '[VALUE]'

Replace [ATTRIBUTE] with the style attribute you want. Remember to remove '-' and make the following letter uppercase.

Examples

document.getElementById('thediv').style.display = 'none'; //changes the display
document.getElementById('thediv').style.paddingLeft = 'none'; //removes padding

document.getElementById("xyz").style.padding-top = '10px';

will be

document.getElementById("xyz").style["paddingTop"] = '10px';

I would recommend using a function, which accepts the element id and an object containing the CSS properties, to handle this. This way you write multiple styles at once and use standard CSS property syntax.

//function to handle multiple styles
function setStyle(elId, propertyObject) {
    var el = document.getElementById(elId);
    for (var property in propertyObject) {
        el.style[property] = propertyObject[property];
    }
}

setStyle('xyz', {'padding-top': '10px'});

Better still you could store the styles in a variable, which will make for much easier property management e.g.

var xyzStyles = {'padding-top':'10px'}
setStyle('xyz', xyzStyles);

Hope that helps

Surprised that I did not see the below query selector way solution,

document.querySelector('#xyz').style.paddingTop = "10px"

CSSStyleDeclaration solutions, an example of the accepted answer

document.getElementById('xyz').style.paddingTop = "10px";

document.getElementById("xyz").setAttribute('style','padding-top:10px');

would also do the job.

document.getElementById('id').style = 'left: 55%; z-index: 999; overflow: hidden; width: 0px; height: 0px; opacity: 0; display: none;';

works for me

I change css style in Javascript function.

But Uncaught TypeError: bild is null .

If I run it in a normal html file it work.

CODE:

  var text = document.getElementById("text");
var bild = document.getElementById("bild");
var container = document.getElementById("container");

bild.style["background-image"] = "url('stock-bild-portrait-of-confident-senior-business-woman-standing-in-office-with-her-arms-crossed-mature-female-1156978234.jpg')";
//bild.style.background-image = "url('stock-bild-portrait-of-confident-senior-business-woman-standing-in-office-with-her-arms-crossed-mature-female-1156978234.jpg')";

 //  bild.style["background-image"] =  "url('" +  defaultpic + "')";
 alert (bild.style["background-image"]) ;
 bild.style["background-size"] = "300px";
 bild.style["background-repeat"] = "no-repeat";
 bild.style["background-position"] = "center";
 bild.style["border-radius"] = "50%";
 bild.style["background-clip"] = "border-box";
 bild.style["transition"] = "background-size 0.2s";
 bild.style["transition-timing-function"] = "cubic-bezier(.07,1.41,.82,1.41)";
 bild.style["display"] = "block";
 bild.style["width"] = "100px";
 bild.style["height"] = "100px";

 bild.style["text-decoration"] = "none";
 bild.style["cursor"] = "pointer";
 bild.style["overflow"] = "hidden";
 bild.style["text-indent"] = "100%";
 bild.style["white-space"] = "nowrap";

 container.style["position"] = "relative";
 container.style["font-family"] = "Arial";

 text.style["position"] = "center";
 text.style["bottom"] = "5px";
 text.style["left"] = "1px";
 text.style["color"] = "white";