给定一个有效 CSS 颜色值的字符串：
需要得到如下格式的数字数组：[R,G,B]
在 JavaScript 中最有效的方法是什么（假设是主流浏览器）？
【问题讨论】：
div 技巧在大多数情况下可能是可以接受的。 OP 确实要求最有效的 方式，但几乎可以肯定是自己解析它。
标签： javascript css performance parsing colors
function parseColor(input) {
var m;
显然，数值比名称更容易解析。所以我们先做这些。
m = input.match(/^#([0-9a-f]{3})$/i)[1];
if( m) {
// in three-character format, each value is multiplied by 0x11 to give an
// even scale from 0x00 to 0xff
return [
parseInt(m.charAt(0),16)*0x11,
parseInt(m.charAt(1),16)*0x11,
parseInt(m.charAt(2),16)*0x11
];
}
这是一个。现在查看完整的六位数格式：
m = input.match(/^#([0-9a-f]{6})$/i)[1];
if( m) {
return [
parseInt(m.substr(0,2),16),
parseInt(m.substr(2,2),16),
parseInt(m.substr(4,2),16)
];
}
现在是rgb() 格式：
m = input.match(/^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
if( m) {
return [m[1],m[2],m[3]];
}
您还可以选择添加对rgba 格式的支持，如果添加HSL2RGB 转换函数，甚至可以添加对hsl/hsla 的支持。
最后，命名颜色。
return ({
"red":[255,0,0],
"yellow":[255,255,0],
// ... and so on. Yes, you have to define ALL the colour codes.
})[input];
并关闭函数：
}
实际上，我不知道我为什么要费心写这些。我刚刚注意到您指定了“假设主要浏览器”，我假设这也意味着“最新”？如果是这样……
function parseColor(input) {
var div = document.createElement('div'), m;
div.style.color = input;
m = getComputedStyle(div).color.match(/^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
if( m) return [m[1],m[2],m[3]];
else throw new Error("Colour "+input+" could not be parsed.");
}
最新的浏览器会将任何给定的颜色转换为其计算样式中的rgb() 格式。把它拿回来，读出来。
【讨论】：
m = ({massive colour map here})[input]; if( m) return m; return [0,0,0];。或者从该函数中抛出一个错误，因为要获得这个条件，任何测试都不应该匹配。
对于兼容 HTML5 的浏览器，我使用指定的值将单个像素写入 <canvas>，然后读回 rgba 四边形。
为了提高性能，我记住了这个函数，这样重复调用相同颜色的字符串就不必执行画布操作了。
EDIT 为 ES6 更新并移除 jQuery 依赖
EDIT (1j01)添加了无效颜色检测，以及支持传递后备颜色的功能
let memoize = function(factory, ctx) {
var cache = {};
return function(key) {
if (!(key in cache)) {
cache[key] = factory.call(ctx, key);
}
return cache[key];
};
};
let colorToRGBA = (function() {
var canvas = document.createElement('canvas');
canvas.width = canvas.height = 1;
var ctx = canvas.getContext('2d');
return memoize(function(col) {
ctx.clearRect(0, 0, 1, 1);
// In order to detect invalid values,
// we can't rely on col being in the same format as what fillStyle is computed as,
// but we can ask it to implicitly compute a normalized value twice and compare.
ctx.fillStyle = '#000';
ctx.fillStyle = col;
var computed = ctx.fillStyle;
ctx.fillStyle = '#fff';
ctx.fillStyle = col;
if (computed !== ctx.fillStyle) {
return; // invalid color
}
ctx.fillRect(0, 0, 1, 1);
return [ ... ctx.getImageData(0, 0, 1, 1).data ];
});
})();
colorToRGBA('white') // [255, 255, 255, 255]
colorToRGBA('blah') // undefined
let colorOrFallbackColorToRGBA = (color, fallbackColor)=> {
// Don't short-circuit getting the fallback RGBA -
// it's already memoized, and we want to show an error
// if the fallback color is invalid even if the main color is valid
var fallbackRGBA = colorToRGBA(fallbackColor);
if (!fallbackRGBA) {
throw new Error(`Invalid fallbackColor ${
fallbackColor != null ? JSON.stringify(fallbackColor) : fallbackColor
}`);
}
return colorToRGBA(color) || fallbackRGBA;
};
colorOrFallbackColorToRGBA('white', 'transparent') // [255, 255, 255, 255]
colorOrFallbackColorToRGBA('blah', 'transparent') // [0, 0, 0, 0]
【讨论】：
$.makeArray，这只是因为 Array 构造函数被破坏（它将单个值视为长度，但多个值作为初始值）
div 解决方案将比 canvas 快得多。
除了@NiettheDarkAbsol 的正确答案，还有一些方面：
backgroundColor 可以是rgb( 3 values ) 或rgba( 4 values)
match 函数很好但是使用正则表达式很昂贵！只要有可能，请改用split。
这个功能更简单快捷：
function parseColor(input) {
return input.split("(")[1].split(")")[0].split(",");
}
好的返回值仍然是字符串，它们包含不需要的空格，但如果在数学表达式中使用，它们会正常工作！
无论如何我都更喜欢这个：它们可以按原样包含：
var bgColors = document.getElementById('myDiv').
backgroundColor.split("(")[1].split(")")[0].split(",");
#RnGnBn 形式（IEx）
rgb(r,g,b)、rgba(r,g,b,a)、#RGB、#RRGGBB 和 #RRRGGGBBB 有一个小而快的功能：
function parseColor(input) {
if (input.substr(0,1)=="#") {
var collen=(input.length-1)/3;
var fact=[17,1,0.062272][collen-1];
return [
Math.round(parseInt(input.substr(1,collen),16)*fact),
Math.round(parseInt(input.substr(1+collen,collen),16)*fact),
Math.round(parseInt(input.substr(1+2*collen,collen),16)*fact)
];
}
else return input.split("(")[1].split(")")[0].split(",").map(x=>+x);
}
function parseColor(input) {
if (input.substr(0,1)=="#") {
var collen=(input.length-1)/3;
var fact=[17,1,0.062272][collen-1];
return [
Math.round(parseInt(input.substr(1,collen),16)*fact),
Math.round(parseInt(input.substr(1+collen,collen),16)*fact),
Math.round(parseInt(input.substr(1+2*collen,collen),16)*fact)
];
}
else return input.split("(")[1].split(")")[0].split(",").map(x=>+x);
}
[ "rgb(123,45,67)", "rgb( 123, 45 , 67 )", "rgba(123,45,67,0.5)", "#F70",
"#FF7700", "#FFF777000", "#FF8000", "#FFF800000", "#F80" ].forEach(
function(color){
colors=parseColor(color);
if (colors.length<4) colors.push('1.0');
document.getElementById('out').innerHTML+=
'<tr><td style="background:'+color+';" />'+
'<td>'+ colors.join('</td><td>')+'</td>'+
'<td>parseColor("'+color+'");</td></tr>';
}
);th { width: 3em; }<table id="out" style="font-family: mono;background:SlateGrey">
<tr><th></th><th>Red</th><th>Green</th><th>Blue</th><th>Alpha</th><th>Code</th></tr>
</table>【讨论】：
#XXX、#XXXXXX 和 #XXXXXXXXX 的非常短的脚本。
虽然 kennebec 已基本完成 Kolink 的回答，但仍有一些改进需要改进。首先，我们可以支持 hsla 和 rgba，这样做最好总是返回一个 alpha 值。另一个小的改进是通过将 trim 方法应用于传入的参数字符串。
function parseColor(color) {
color = color.trim().toLowerCase();
color = _colorsByName[color] || color;
var hex3 = color.match(/^#([0-9a-f]{3})$/i);
if (hex3) {
hex3 = hex3[1];
return [
parseInt(hex3.charAt(0),16)*0x11,
parseInt(hex3.charAt(1),16)*0x11,
parseInt(hex3.charAt(2),16)*0x11, 1
];
}
var hex6 = color.match(/^#([0-9a-f]{6})$/i);
if (hex6) {
hex6 = hex6[1];
return [
parseInt(hex6.substr(0,2),16),
parseInt(hex6.substr(2,2),16),
parseInt(hex6.substr(4,2),16), 1
];
}
var rgba = color.match(/^rgba\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+.*\d*)\s*\)$/i) || color.match(/^rgba\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
if( rgba ) {
return [rgba[1],rgba[2],rgba[3], rgba[4]===undefined?1:rgba[4]];
}
var rgb = color.match(/^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
if( rgb ) {
return [rgb[1],rgb[2],rgb[3],1];
}
if(color.indexOf('hsl')== 0)
return _hslToRgb(color);
}
function _hslToRgb(hsl){
if(typeof hsl== 'string'){
hsl= hsl.match(/(\d+(\.\d+)?)/g);
}
var sub, h= hsl[0]/360, s= hsl[1]/100, l= hsl[2]/100, a = hsl[3]===undefined?1:hsl[3], t1, t2, t3, rgb, val;
if(s== 0){
val= Math.round(l*255);
rgb= [val, val, val, a];
}
else{
if(l<0.5)
t2= l*(1 + s);
else
t2= l + s - l*s;
t1 = 2*l - t2;
rgb = [0, 0, 0];
for(var i=0; i<3; i++){
t3 = h + 1/3 * -(i - 1);
t3 < 0 && t3++;
t3 > 1 && t3--;
if (6 * t3 < 1)
val= t1 + (t2 - t1) * 6 * t3;
else if (2 * t3 < 1)
val= t2;
else if (3*t3<2)
val = t1 + (t2 - t1) * (2 / 3 - t3) * 6;
else
val= t1;
rgb[i] = Math.round(val*255);
}
}
rgb.push(a);
return rgb;
}
var _colorsByName = {aliceblue:"#f0f8ff",antiquewhite:"#faebd7",aqua:"#00ffff",aquamarine:"#7fffd4",azure:"#f0ffff",beige:"#f5f5dc",bisque:"#ffe4c4",
black:"#000000",blanchedalmond:"#ffebcd",blue:"#0000ff",blueviolet:"#8a2be2",brown:"#a52a2a",burlywood:"#deb887",cadetblue:"#5f9ea0",
chartreuse:"#7fff00",chocolate:"#d2691e",coral:"#ff7f50",cornflowerblue:"#6495ed",cornsilk:"#fff8dc",crimson:"#dc143c",cyan:"#00ffff",
darkblue:"#00008b",darkcyan:"#008b8b",darkgoldenrod:"#b8860b",darkgray:"#a9a9a9",darkgreen:"#006400",darkkhaki:"#bdb76b",
darkmagenta:"#8b008b",darkolivegreen:"#556b2f",darkorange:"#ff8c00",darkorchid:"#9932cc",darkred:"#8b0000",darksalmon:"#e9967a",
darkseagreen:"#8fbc8f",darkslateblue:"#483d8b",darkslategray:"#2f4f4f",darkturquoise:"#00ced1",darkviolet:"#9400d3",deeppink:"#ff1493",
deepskyblue:"#00bfff",dimgray:"#696969",dodgerblue:"#1e90ff",firebrick:"#b22222",floralwhite:"#fffaf0",forestgreen:"#228b22",
fuchsia:"#ff00ff",gainsboro:"#dcdcdc",ghostwhite:"#f8f8ff",gold:"#ffd700",goldenrod:"#daa520",gray:"#808080",green:"#008000",
greenyellow:"#adff2f",honeydew:"#f0fff0",hotpink:"#ff69b4",indianred :"#cd5c5c",indigo :"#4b0082",ivory:"#fffff0",khaki:"#f0e68c",
lavender:"#e6e6fa",lavenderblush:"#fff0f5",lawngreen:"#7cfc00",lemonchiffon:"#fffacd",lightblue:"#add8e6",lightcoral:"#f08080",
lightcyan:"#e0ffff",lightgoldenrodyellow:"#fafad2",lightgray:"#d3d3d3",lightgreen:"#90ee90",lightpink:"#ffb6c1",lightsalmon:"#ffa07a",
lightseagreen:"#20b2aa",lightskyblue:"#87cefa",lightslategray:"#778899",lightsteelblue:"#b0c4de",lightyellow:"#ffffe0",lime:"#00ff00",
limegreen:"#32cd32",linen:"#faf0e6",magenta:"#ff00ff",maroon:"#800000",mediumaquamarine:"#66cdaa",mediumblue:"#0000cd",
mediumorchid:"#ba55d3",mediumpurple:"#9370db",mediumseagreen:"#3cb371",mediumslateblue:"#7b68ee",mediumspringgreen:"#00fa9a",
mediumturquoise:"#48d1cc",mediumvioletred:"#c71585",midnightblue:"#191970",mintcream:"#f5fffa",mistyrose:"#ffe4e1",moccasin:"#ffe4b5",
navajowhite:"#ffdead",navy:"#000080",oldlace:"#fdf5e6",olive:"#808000",olivedrab:"#6b8e23",orange:"#ffa500",orangered:"#ff4500",
orchid:"#da70d6",palegoldenrod:"#eee8aa",palegreen:"#98fb98",paleturquoise:"#afeeee",palevioletred:"#db7093",papayawhip:"#ffefd5",
peachpuff:"#ffdab9",peru:"#cd853f",pink:"#ffc0cb",plum:"#dda0dd",powderblue:"#b0e0e6",purple:"#800080",red:"#ff0000",rosybrown:"#bc8f8f",
royalblue:"#4169e1",saddlebrown:"#8b4513",salmon:"#fa8072",sandybrown:"#f4a460",seagreen:"#2e8b57",seashell:"#fff5ee",sienna:"#a0522d",
silver:"#c0c0c0",skyblue:"#87ceeb",slateblue:"#6a5acd",slategray:"#708090",snow:"#fffafa",springgreen:"#00ff7f",steelblue:"#4682b4",
tan:"#d2b48c",teal:"#008080",thistle:"#d8bfd8",tomato:"#ff6347",turquoise:"#40e0d0",violet:"#ee82ee",wheat:"#f5deb3",white:"#ffffff",
whitesmoke:"#f5f5f5",yellow:"#ffff00",yellowgreen:"#9acd32"
};
【讨论】：
// 这将为您发布的样本返回一个 [red.green,blue] 十进制数组，加上 rgb 百分比。
// 它忽略透明度、hsl 和大多数浏览器支持的扩展颜色名称集：
function getRgb(c){
c= c.toLowerCase();
if (/^[a-z]+$/.test(c)){
var colornames={
aqua:'#00ffff', black:'#000000', blue:'#0000ff', fuchsia:'#ff00ff',
gray:'#808080', green:'#008000', lime:'#00ff00', maroon:'#800000',
navy:'#000080', olive:'#808000', orange:'#ffa500', purple:'#800080',
red:'#ff0000', silver:'#c0c0c0', teal:'#008080', white:'#ffffff',
yellow:'#ffff00'
}
c= colornames[c];
}
if(/^#([a-f0-9]{3}){1,2}$/.test(c)){
if(c.length== 4){
c= '#'+[c[1], c[1], c[2], c[2], c[3], c[3]].join('');
}
c= '0x'+c.substring(1);
return [(c>>16)&255, (c>>8)&255, c&255];
}
else if(c.indexOf('rgb')== 0){
c= c.match(/\d+(\.\d+)?%?/g);
if(c){
for(var i= 0;i<3;i++){
if(c[i].indexOf('%')!= -1){
c[i]= Math.round(parseFloat(c[i])*2.55);
}
if(c[i]<0) c[i]= 0;
if(c[i]>255) c[i]= 255;
}
return c;
}
}
}
//这个版本会为大多数颜色字符串返回一个[red.green,blue]十进制数组，忽略透明度。
function getRgb2(c){
c= c.toLowerCase();
var colornames={
aliceblue:'#f0f8ff', antiquewhite:'#faebd7', aqua:'#00ffff',
aquamarine:'#7fffd4', azure:'#f0ffff', beige:'#f5f5dc',
bisque:'#ffe4c4', black:'#000000', blanchedalmond:'#ffebcd',
blue:'#0000ff', blueviolet:'#8a2be2', brown:'#a52a2a',
burlywood:'#deb887', cadetblue:'#5f9ea0', chartreuse:'#7fff00',
chocolate:'#d2691e', coral:'#ff7f50', cornflowerblue:'#6495ed',
cornsilk:'#fff8dc', crimson:'#dc143c', cyan:'#00ffff',
darkblue:'#00008b', darkcyan:'#008b8b', darkgoldenrod:'#b8860b',
darkgray:'#a9a9a9', darkgreen:'#006400', darkkhaki:'#bdb76b',
darkmagenta:'#8b008b', darkolivegreen:'#556b2f', darkorange:'#ff8c00',
darkorchid:'#9932cc', darkred:'#8b0000', darksalmon:'#e9967a',
darkseagreen:'#8fbc8f', darkslateblue:'#483d8b', darkslategray:'#2f4f4f',
darkturquoise:'#00ced1', darkviolet:'#9400d3', deeppink:'#ff1493',
deepskyblue:'#00bfff', dimgray:'#696969', dodgerblue:'#1e90ff',
firebrick:'#b22222', floralwhite:'#fffaf0',
forestgreen:'#228b22', fuchsia:'#ff00ff', gainsboro:'#dcdcdc',
ghostwhite:'#f8f8ff', gold:'#ffd700', goldenrod:'#daa520', gray:'#808080',
green:'#008000', greenyellow:'#adff2f', honeydew:'#f0fff0',
hotpink:'#ff69b4', indianred:'#cd5c5c', indigo:'#4b0082',
ivory:'#fffff0', khaki:'#f0e68c', lavender:'#e6e6fa',
lavenderblush:'#fff0f5', lawngreen:'#7cfc00', lemonchiffon:'#fffacd',
lightblue:'#add8e6', lightcoral:'#f08080', lightcyan:'#e0ffff',
lightgoldenrodyellow:'#fafad2', lightgray:'#d3d3d3', lightgreen:'#90ee90',
lightpink:'#ffb6c1', lightsalmon:'#ffa07a', lightseagreen:'#20b2aa',
lightskyblue:'#87cefa', lightslategray:'#778899', lightsteelblue:'#b0c4de',
lightyellow:'#ffffe0', lime:'#00ff00', limegreen:'#32cd32', linen:'#faf0e6',
magenta:'#ff00ff', maroon:'#800000', mediumaquamarine:'#66cdaa',
mediumblue:'#0000cd', mediumorchid:'#ba55d3', mediumpurple:'#9370db',
mediumseagreen:'#3cb371', mediumslateblue:'#7b68ee',
mediumspringgreen:'#00fa9a', mediumturquoise:'#48d1cc',
mediumvioletred:'#c71585', midnightblue:'#191970', mintcream:'#f5fffa',
mistyrose:'#ffe4e1', moccasin:'#ffe4b5', navajowhite:'#ffdead',
navy:'#000080', oldlace:'#fdf5e6', olive:'#808000', olivedrab:'#6b8e23',
orange:'#ffa500', orangered:'#ff4500', orchid:'#da70d6',
alegoldenrod:'#eee8aa', palegreen:'#98fb98', paleturquoise:'#afeeee',
palevioletred:'#db7093', papayawhip:'#ffefd5', peachpuff:'#ffdab9',
peru:'#cd853f', pink:'#ffc0cb', plum:'#dda0dd', powderblue:'#b0e0e6',
purple:'#800080', red:'#ff0000', rosybrown:'#bc8f8f', royalblue:'#4169e1',
saddlebrown:'#8b4513', salmon:'#fa8072', sandybrown:'#f4a460',
seagreen:'#2e8b57', seashell:'#fff5ee', sienna:'#a0522d',
silver:'#c0c0c0', skyblue:'#87ceeb', slateblue:'#6a5acd',
slategray:'#708090', snow:'#fffafa', springgreen:'#00ff7f',
steelblue:'#4682b4', tan:'#d2b48c', teal:'#008080', thistle:'#d8bfd8',
tomato:'#ff6347', turquoise:'#40e0d0', violet:'#ee82ee', wheat:'#f5deb3',
white:'#ffffff', whitesmoke:'#f5f5f5', yellow:'#ffff00', yellowgreen:'#9acd32'
}
if (/^[a-z]+$/.test(c)){
c= colornames[c];
}
if(/^#([a-f0-9]{3}){1,2}$/.test(c)){
if(c.length== 4){
c= '#'+[c[1], c[1], c[2], c[2], c[3], c[3]].join('');
}
c= '0x'+c.substring(1);
return [(c>>16)&255, (c>>8)&255, c&255];
}
if(c.indexOf('hsl')== 0) return hslToRgb(c);
else{
c= c.match(/\d+(\.\d+)?%?/g);
if(c){
for(var i= 0;i<3;i++){
if(c[i].indexOf('%')!= -1) c[i]= parseFloat(c[i])*2.55;
c[i]= Math.round(c[i]);
if(c[i]<0) c[i]= 0;
if(c[i]>255) c[i]= 255;
}
return c;
}
}
function hslToRgb(hsl){
if(typeof hsl== 'string'){
hsl= hsl.match(/(\d+(\.\d+)?)/g);
}
var sub, h= hsl[0]/360, s= hsl[1]/100, l= hsl[2]/100,
t1, t2, t3, rgb, val;
if(s== 0){
val= Math.round(l*255);
rgb= [val, val, val];
}
else{
if(l<0.5) t2= l*(1 + s);
else t2= l + s - l*s;
t1= 2*l - t2;
rgb= [0, 0, 0];
for(var i= 0;i<3;i++){
t3= h + 1/3*-(i - 1);
t3<0 && t3++;
t3>1 && t3--;
if(6*t3<1) val= t1 +(t2 - t1)*6*t3;
else if(2*t3<1) val= t2;
else if(3*t3<2) val= t1 +(t2 - t1)*(2/3 - t3)*6;
else val= t1;
rgb[i]= Math.round(val*255);
}
}
return rgb;
}
}
【讨论】：
// 是怎么回事？习惯的力量？
死灵术。
对于任何真正需要它的人，这里有完整的工作和功能完整的代码。
将其视为对“Niet the Dark Absol”答案的补充
干杯。
function parseColor(input) {
var mm;
var m;
// Obviously, the numeric values will be easier to parse than names.So we do those first.
mm = input.match(/^#?([0-9a-f]{3})$/i);
if (mm) {
m = mm[1];
// in three-character format, each value is multiplied by 0x11 to give an
// even scale from 0x00 to 0xff
return [
parseInt(m.charAt(0), 16) * 0x11,
parseInt(m.charAt(1), 16) * 0x11,
parseInt(m.charAt(2), 16) * 0x11
];
}
// That's one. Now for the full six-digit format:
mm = input.match(/^#?([0-9a-f]{6})$/i);
if (mm) {
m = mm[1];
return [
parseInt(m.substr(0, 2), 16),
parseInt(m.substr(2, 2), 16),
parseInt(m.substr(4, 2), 16)
];
}
// And now for rgb() format:
var mm = input.match(/^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
if (mm) {
return [mm[1], mm[2], mm[3]];
}
// https://www.w3schools.com/colors/colors_names.asp
// https://en.wikipedia.org/wiki/Web_colors
// http://www.colors.commutercreative.com/grid/
var webColors = {
"AliceBlue": "#F0F8FF",
"AntiqueWhite": "#FAEBD7",
"Aqua": "#00FFFF",
"Aquamarine": "#7FFFD4",
"Azure": "#F0FFFF",
"Beige": "#F5F5DC",
"Bisque": "#FFE4C4",
"Black": "#000000",
"BlanchedAlmond": "#FFEBCD",
"Blue": "#0000FF",
"BlueViolet": "#8A2BE2",
"Brown": "#A52A2A",
"BurlyWood": "#DEB887",
"CadetBlue": "#5F9EA0",
"Chartreuse": "#7FFF00",
"Chocolate": "#D2691E",
"Coral": "#FF7F50",
"CornflowerBlue": "#6495ED",
"Cornsilk": "#FFF8DC",
"Crimson": "#DC143C",
"Cyan": "#00FFFF",
"DarkBlue": "#00008B",
"DarkCyan": "#008B8B",
"DarkGoldenRod": "#B8860B",
"DarkGray": "#A9A9A9",
"DarkGrey": "#A9A9A9",
"DarkGreen": "#006400",
"DarkKhaki": "#BDB76B",
"DarkMagenta": "#8B008B",
"DarkOliveGreen": "#556B2F",
"DarkOrange": "#FF8C00",
"DarkOrchid": "#9932CC",
"DarkRed": "#8B0000",
"DarkSalmon": "#E9967A",
"DarkSeaGreen": "#8FBC8F",
"DarkSlateBlue": "#483D8B",
"DarkSlateGray": "#2F4F4F",
"DarkSlateGrey": "#2F4F4F",
"DarkTurquoise": "#00CED1",
"DarkViolet": "#9400D3",
"DeepPink": "#FF1493",
"DeepSkyBlue": "#00BFFF",
"DimGray": "#696969",
"DimGrey": "#696969",
"DodgerBlue": "#1E90FF",
"FireBrick": "#B22222",
"FloralWhite": "#FFFAF0",
"ForestGreen": "#228B22",
"Fuchsia": "#FF00FF",
"Gainsboro": "#DCDCDC",
"GhostWhite": "#F8F8FF",
"Gold": "#FFD700",
"GoldenRod": "#DAA520",
"Gray": "#808080",
"Grey": "#808080",
"Green": "#008000",
"GreenYellow": "#ADFF2F",
"HoneyDew": "#F0FFF0",
"HotPink": "#FF69B4",
"IndianRed ": "#CD5C5C",
"Indigo ": "#4B0082",
"Ivory": "#FFFFF0",
"Khaki": "#F0E68C",
"Lavender": "#E6E6FA",
"LavenderBlush": "#FFF0F5",
"LawnGreen": "#7CFC00",
"LemonChiffon": "#FFFACD",
"LightBlue": "#ADD8E6",
"LightCoral": "#F08080",
"LightCyan": "#E0FFFF",
"LightGoldenRodYellow": "#FAFAD2",
"LightGray": "#D3D3D3",
"LightGrey": "#D3D3D3",
"LightGreen": "#90EE90",
"LightPink": "#FFB6C1",
"LightSalmon": "#FFA07A",
"LightSeaGreen": "#20B2AA",
"LightSkyBlue": "#87CEFA",
"LightSlateGray": "#778899",
"LightSlateGrey": "#778899",
"LightSteelBlue": "#B0C4DE",
"LightYellow": "#FFFFE0",
"Lime": "#00FF00",
"LimeGreen": "#32CD32",
"Linen": "#FAF0E6",
"Magenta": "#FF00FF",
"Maroon": "#800000",
"MediumAquaMarine": "#66CDAA",
"MediumBlue": "#0000CD",
"MediumOrchid": "#BA55D3",
"MediumPurple": "#9370DB",
"MediumSeaGreen": "#3CB371",
"MediumSlateBlue": "#7B68EE",
"MediumSpringGreen": "#00FA9A",
"MediumTurquoise": "#48D1CC",
"MediumVioletRed": "#C71585",
"MidnightBlue": "#191970",
"MintCream": "#F5FFFA",
"MistyRose": "#FFE4E1",
"Moccasin": "#FFE4B5",
"NavajoWhite": "#FFDEAD",
"Navy": "#000080",
"OldLace": "#FDF5E6",
"Olive": "#808000",
"OliveDrab": "#6B8E23",
"Orange": "#FFA500",
"OrangeRed": "#FF4500",
"Orchid": "#DA70D6",
"PaleGoldenRod": "#EEE8AA",
"PaleGreen": "#98FB98",
"PaleTurquoise": "#AFEEEE",
"PaleVioletRed": "#DB7093",
"PapayaWhip": "#FFEFD5",
"PeachPuff": "#FFDAB9",
"Peru": "#CD853F",
"Pink": "#FFC0CB",
"Plum": "#DDA0DD",
"PowderBlue": "#B0E0E6",
"Purple": "#800080",
"RebeccaPurple": "#663399",
"Red": "#FF0000",
"RosyBrown": "#BC8F8F",
"RoyalBlue": "#4169E1",
"SaddleBrown": "#8B4513",
"Salmon": "#FA8072",
"SandyBrown": "#F4A460",
"SeaGreen": "#2E8B57",
"SeaShell": "#FFF5EE",
"Sienna": "#A0522D",
"Silver": "#C0C0C0",
"SkyBlue": "#87CEEB",
"SlateBlue": "#6A5ACD",
"SlateGray": "#708090",
"SlateGrey": "#708090",
"Snow": "#FFFAFA",
"SpringGreen": "#00FF7F",
"SteelBlue": "#4682B4",
"Tan": "#D2B48C",
"Teal": "#008080",
"Thistle": "#D8BFD8",
"Tomato": "#FF6347",
"Turquoise": "#40E0D0",
"Violet": "#EE82EE",
"Wheat": "#F5DEB3",
"White": "#FFFFFF",
"WhiteSmoke": "#F5F5F5",
"Yellow": "#FFFF00",
"YellowGreen": "#9ACD32"
};
for (var p in webColors) {
webColors[p.toLowerCase()] = webColors[p];
}
var wc = webColors[input.toLowerCase()];
if (wc != null)
return parseColor(wc);
console.log(input);
throw Error("'" + input + "' is not a valid color...");
}
// parseColor("steelblue");
parseColor("SteelBlue");
// JSON.stringify(webColors, null, 2);
// JSON.stringify(lcWebColors, null, 2);
//# sourceMappingURL=colorInfluence.js.map
【讨论】：
let 而不是var；或者更好的是，您可以在这里大量使用const。 2. 您不再需要在函数顶部声明变量。这不是 1998 年。 3. 你的小写逻辑全错了。例如。 BLUE 不起作用，但它应该起作用。您应该在 lookup 上将颜色小写，不要只将所有小写名称添加到地图中。 IE。 const we = webColors[input.toLowerCase()].
简化@NicolasL 的答案（反过来又受到@Niet_the_Dark_Absol 的启发）
我得到了这个基于浏览器的简单而简短的解决方案：
function parseCssColor(str) {
const div = document.createElement("div");
document.body.appendChild(div);
div.style.color = str;
const res = getComputedStyle(div).color.match(/[\.\d]+/g).map(Number);
div.remove();
return res;
}
parseCssColor("lightblue") // [173, 216, 230]
parseCssColor("#663399") // [102, 51, 153]
parseCssColor("#aa11bb22") // [170, 17, 187, 0.133]
【讨论】：
对于 hsl 和 rgb 这两种颜色都有效：
input.replace(/[a-z%\s\(\)]/g,'').split(',')
【讨论】：
用这个漂亮的getComputedStyle hack 尝试@Niet_the_Dark_Absol 的答案，直到将创建的元素（Chrome 69 和 Firefox 75）附加到 DOM 之前，我一直无法使其工作。
由于我还希望能够处理 Alpha 通道值（透明度），所以我修改了 Regex 并返回了结果。
如果它可以对任何人有任何帮助，这是我的功能：
function colorToRgbParser(cssColor) {
const div = document.createElement('div');
div.id = 'for-computed-style';
div.style.color = cssColor;
// appending the created element to the DOM
document.querySelector('body').appendChild(div);
const match = getComputedStyle(div).color.match(/^rgba?\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*(?:,\s*(\d\.\d)\s*)?\)$/i);
// removing element from the DOM
document.querySelector('#for-computed-style').remove();
if (match) {
// match[0] is regex complete match (e.g. "rgb(0,0,0)"), not a regex capturing group
let parsedColor = {
r: match[1],
g: match[2],
b: match[3]
};
if (match[4]) { // if alpha channel is present
parsedColor.a = match[4];
}
return parsedColor;
} else {
throw new Error(`Color ${cssColor} could not be parsed.`);
}
}
【讨论】：
我来这里是为了同样的问题。但是在阅读了所有这些方法（以及它们在所有情况下错误或不起作用的地方）之后，我决定去图书馆。
除了在大多数情况下解析颜色之外，您还想对它做一些事情。
如果像我一样，您对“高效”的定义是“错误更少且开箱即用”，我建议使用 chroma.js。
使用 npm install chroma-js 安装它（不是 chrome-js，不是 chroma）
chroma('pink').darken().saturate(2).rgb()
【讨论】：
var input = '#FFF';
var color = input.toLowerCase();
var hex = ['0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'];
var rgb = [];
if(/#/.test(color))
if(color.length==4){
var parsed = color.match(/\w/g);
rgb = [
hex.indexOf(parsed[0])*16+hex.indexOf(parsed[0]),
hex.indexOf(parsed[1])*16+hex.indexOf(parsed[1]),
hex.indexOf(parsed[2])*16+hex.indexOf(parsed[2])
]
}else{
var parsed = color.match(/\w{2}/g);
rgb = [
hex.indexOf(parsed[0][0])*16+hex.indexOf(parsed[0][1]),
hex.indexOf(parsed[1][0])*16+hex.indexOf(parsed[1][1]),
hex.indexOf(parsed[2][0])*16+hex.indexOf(parsed[2][1])
]
}
else if(/(rgb)/.test(color))
rgb = color.match(/\d+/g);
else{
//Here you define all the colors, like 'blue': [0,0,255]
}
例如，如果您尝试获取元素的背景颜色，则可以使用：
var bg = getComputedStyle(myElem,null).getPropertyValue('background-color');
var rgb = match(/\d+/g).slice(0,3);
【讨论】：
hex.indexOf(parsed[0]) ha 这是一种非常有趣（而且很糟糕！）的方法。