jQuery将CSS颜色设置为HEX而不是RGB

Question

I am trying to create a jQuery hook which will read and set all colors as hex values instead of RGB. I have found a hook that will properly read the color as HEX but I am not sure on how to modify it to write CSS colors as HEX.

So for example I would like $("h1").css('color', '#333333'); to inline style h1's with "style='color:#333333;'" instead of the current RGB equivalent. The hook I am using to return read colors as hex is:

$.cssHooks.color = {
get: function(elem) {
    if (elem.currentStyle)
        var bg = elem.currentStyle["color"];
    else if (window.getComputedStyle)
        var bg = document.defaultView.getComputedStyle(elem,
            null).getPropertyValue("color");
    if (bg.search("rgb") == -1)
        return bg;
    else {
        bg = bg.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
        function hex(x) {
            return ("0" + parseInt(x).toString(16)).slice(-2);
        }
        return "#" + hex(bg[1]) + hex(bg[2]) + hex(bg[3]);
    }
}}

Update

I was able to accomplish it in a super roundabout way by getting all the elements styles converting any colors to HEX and the rebuilding the styles and setting it via $(elm).attr(style, styles); Seems very hacky and convoluted but it works.

Answer 1

This method seems to work for me, but it assumes a well formatted string. You could add your checks to this function:

function rgb_to_hex(rgb_color) {
    if (!rgb_color) return ''
    return rgb_color
        .replace(/.*rgba?\(([^(]+)\).*/gi, '$1')
        .split(',')
        .splice(0,3)
        .reduce(function(acc, cur) { return acc+format_hex(cur) }, '');
}

function format_hex(ns) {
    var v;
    return isNaN(v = parseInt(ns)) ? '' : ('00' + v.toString(16)).substr(-2);
}

var v,
    color1 = (v = rgb_to_hex('rgb(0,0,0)')) !== '' ?  '#' + v : '',
    color2 = (v = rgb_to_hex('rgb(0,255,0)')) !== '' ?  '#' + v : '',
    color3 = (v = rgb_to_hex('rgba(123,39,12, .1)')) !== '' ?  '#' + v : '',
    color4 = (v = rgb_to_hex()) !== '' ?  '#' + v : '';
    color5 = (v = rgb_to_hex('gobbledegook')) !== '' ?  '#' + v : '';
console.log(color1); // '#000000'
console.log(color2); // '#00ff00'
console.log(color3); // '#7b270c'
console.log(color4); // ''
console.log(color5); // ''

Also, this portion:

if (elem.currentStyle)
    var bg = elem.currentStyle["color"];
else if (window.getComputedStyle)
    var bg = document.defaultView.getComputedStyle(elem, null)
        .getPropertyValue("color");

should be something like:

var bg = '';
if (elem.currentStyle) {
    bg = elem.currentStyle["color"];
} else if (window.getComputedStyle) {
    bg = document.defaultView.getComputedStyle(elem, null)
        .getPropertyValue("color");
}

because bg might not be defined.

Answer 2

The problem you have is that jQuery doesn't write what you wants, but what it understands. You can "force" the code do what you want like this:

$('h1').css('color', '');
$('h1').attr('style', $('h1').attr('style') + 'color: #FFEE02');

You must use the first line in order to don't make your html code grow so much, and in the second line, you set the color over the html.