Set CSS property in Javascript?

2019-01-02 16:30发布

问题:

I've created the following...

var menu = document.createElement('select');

How would I now set CSS attributes e.g width: 100px?

回答1:

Use element.style:

var element = document.createElement('select');
element.style.width = "100px";


回答2:

Just set the style:

var menu = document.createElement("select");
menu.style.width = "100px";

Or if you like, you can use jQuery:

$(menu).css("width", "100px");


回答3:

For most styles do this:

var obj = document.createElement('select');
obj.style.width= "100px";

For styles that have hyphens in the name do this instead:

var obj = document.createElement('select');
obj.style["-webkit-background-size"] = "100px"


回答4:

All of the answers tell you correctly how to do what you asked but I would advise using JavaScript to set a class on the element and style it by using CSS. That way you are keeping the correct separation between behaviour and style.

Imagine if you got a designer in to re-style the site... they should be able to work purely in CSS without having to work with your JavaScript.

In prototype I would do:

$(newElement).addClassName('blah')


回答5:

That's actually quite simple with vanilla JavaScript:

menu.style.width = "100px";


回答6:

if you want to add a global property, you can use:

    var styleEl = document.createElement('style'), styleSheet;
            document.head.appendChild(styleEl);
            styleSheet = styleEl.sheet;
            styleSheet.insertRule(".modal { position:absolute; bottom:auto; }", 0);


回答7:

When debugging, I like to be able to add a bunch of css attributes in one line:

menu.style.cssText = 'width: 100px';

Getting used to this style you can add a bunch of css in one line like so:

menu.style.cssText = 'width: 100px; height: 100px; background: #afafaf';


回答8:

<h1>Silence and Smile</h1>
<input  type="button"  value="Show Red"   onclick="document.getElementById('h1').style.color='Red'"/>
<input  type="button"  value="Show Green" onclick="document.getElementById('h1').style.color='Green'"/>


回答9:

Just for people who want to doing the same thing in 2018

You can assign a CSS custom property to your element (through CSS or JS) and change it:

Assigment through CSS:

element {
  --element-width: 300px;

  width: var(--element-width, 100%);
}

Assignment through JS

ELEMENT.style.setProperty('--element-width', NEW_VALUE);

Get property value through JS

ELEMENT.style.getPropertyValue('--element-width');

Here useful links:

  • https://developer.mozilla.org/en-US/docs/Web/CSS/--*
  • https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/getPropertyValue
  • https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/setProperty
  • https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/removeProperty


回答10:

<body>
  <h1 id="h1">Silence and Smile</h1><br />
  <h3 id="h3">Silence and Smile</h3>

  <script type="text/javascript">
    document.getElementById("h1").style.color = "Red";
    document.getElementById("h1").style.background = "Green";
    document.getElementById("h3").style.fontSize = "larger" ; 
    document.getElementById("h3").style.fontFamily = "Arial";
  </script>
</body>


回答11:

This works well with most CSS properties if there are no hyphens in them.

var element = document.createElement('select');
element.style.width = "100px";

For properties with hyphens in them like max-width, you should convert the sausage-case to camelCase

var element = document.createElement('select');
element.style.maxWidth = "100px";


标签: