CSS 将百分比转换为像素

Question

I have "div" element with specified width and height expressed in percents in CSS.
I would like to get by JS script its width and height expressed in pixels. It's even possible?

Answer 1

You can use

el.clientHeight;
el.clientWidth;

( el is a reference to the element)

Demo

Note those properties were first introduced in the MS IE DHTML object model. More recently they were standardized in CSSOM View Module , W3C Working Draft 22 February 2008.

Those properties were widely supported. However, it's possible than an old non-MS compliant browser doesn't support them. In those cases, you can use getComputedStyle :

function findSize(el, size) {
    /* size must be 'width' or ' height' */
    return window.getComputedStyle
        ? getComputedStyle(el,null).getPropertyValue(size)
        : el['client'+size.substr(0,1).toUpperCase() + size.substr(1)] + 'px';
}
findSize(el, 'width');
findSize(el, 'height');

Demo

Browser support of getComputedStyle and clientHeight / clientWidth way is at least:

                 | IE  | Firefox | Chrome | Safari | Opera
-----------------|-----------------------------------------
getComputedStyle | 9   | <=3     | 1      | <=4    | <=10
client           | <=5 | <=3     | 1      | <=4    | <=10

^{( <=n means that it's supported at least from version n , but I couldn't test previous versions)}

Answer 2

Use window.getComputedStyle() for this

<div style="wdith:50%">50% width</div>​​​​​​​​​​​​​

(function() {
    var div = document.getElementsByTagName("div")[0];

    console.log(window.getComputedStyle(div, null)["width"]);
}())​

fiddle

Supported by all major browsers and IE9+. For lower versions of IE have a look at currentStyle

Answer 3

Have a look at This .

The jQuery key is :

$("#div").width();

Answer 4

jQuery 键是：

$("#div").width($("#div").width());