如何将颜色在RGB格式转换为十六进制格式,反之亦然?
例如,将'#0080C0'转换为(0,128,192)。
如何将颜色在RGB格式转换为十六进制格式,反之亦然?
例如,将'#0080C0'转换为(0,128,192)。
当前回答
你想要这样的东西吗?
function RGB2HTML(red, green, blue)
{
return '#' + red.toString(16) +
green.toString(16) +
blue.toString(16);
}
alert(RGB2HTML(150, 135, 200));
显示# 9687 c8
其他回答
以下是我的看法:
function rgbToHex(red, green, blue) {
const rgb = (red << 16) | (green << 8) | (blue << 0);
return '#' + (0x1000000 + rgb).toString(16).slice(1);
}
function hexToRgb(hex) {
const normal = hex.match(/^#([0-9a-f]{2})([0-9a-f]{2})([0-9a-f]{2})$/i);
if (normal) return normal.slice(1).map(e => parseInt(e, 16));
const shorthand = hex.match(/^#([0-9a-f])([0-9a-f])([0-9a-f])$/i);
if (shorthand) return shorthand.slice(1).map(e => 0x11 * parseInt(e, 16));
return null;
}
哇。这些答案都不能处理分数的边缘情况,等等。当r, g, b为零时,位移版本也不起作用。
这是一个可以处理r g b是小数的版本。它对颜色之间的插值很有用,所以我也包括了这段代码。但它仍然不能处理r, g, b在0-255范围之外的情况
/**
* Operates with colors.
* @class Q.Colors
*/
Q.Color = {
/**
* Get a color somewhere between startColor and endColor
* @method toHex
* @static
* @param {String|Number} startColor
* @param {String|Number} endColor
* @param {String|Number} fraction
* @returns {String} a color as a hex string without '#' in front
*/
toHex: function (r, g, b) {
return [r, g, b].map(x => {
const hex = Math.round(x).toString(16)
return hex.length === 1 ? '0' + hex : hex
}).join('');
},
/**
* Get a color somewhere between startColor and endColor
* @method between
* @static
* @param {String|Number} startColor
* @param {String|Number} endColor
* @param {String|Number} fraction
* @returns {String} a color as a hex string without '#' in front
*/
between: function(startColor, endColor, fraction) {
if (typeof startColor === 'string') {
startColor = parseInt(startColor.replace('#', '0x'), 16);
}
if (typeof endColor === 'string') {
endColor = parseInt(endColor.replace('#', '0x'), 16);
}
var startRed = (startColor >> 16) & 0xFF;
var startGreen = (startColor >> 8) & 0xFF;
var startBlue = startColor & 0xFF;
var endRed = (endColor >> 16) & 0xFF;
var endGreen = (endColor >> 8) & 0xFF;
var endBlue = endColor & 0xFF;
var newRed = startRed + fraction * (endRed - startRed);
var newGreen = startGreen + fraction * (endGreen - startGreen);
var newBlue = startBlue + fraction * (endBlue - startBlue);
return Q.Color.toHex(newRed, newGreen, newBlue);
},
/**
* Sets a new theme-color on the window
* @method setWindowTheme
* @static
* @param {String} color in any CSS format, such as "#aabbcc"
* @return {String} the previous color
*/
setWindowTheme: function (color) {
var meta = document.querySelector('meta[name="theme-color"]');
var prevColor = null;
if (meta) {
prevColor = meta.getAttribute('content');
}
if (color) {
if (!meta) {
meta = document.createElement('meta');
meta.setAttribute('name', 'theme-color');
}
meta.setAttribute('content', color);
}
return prevColor;
},
/**
* Gets the current window theme color
* @method getWindowTheme
* @static
* @param {String} color in any CSS format, such as "#aabbcc"
* @return {String} the previous color
*/
getWindowTheme: function () {
var meta = document.querySelector('meta[name="theme-color"]');
return meta.getAttribute('content');
}
}
CSS Level 4边注:一般来说,你想要能够将十六进制转换为RGB的原因是alpha通道,在这种情况下,你可以很快用CSS4添加一个十六进制。例如:#FF8800FF或#f80f表示全透明的橙色。
除此之外,下面的代码在一个函数中回答了这两个问题,从另一个函数到另一个函数。这接受一个可选的alpha通道,支持字符串数组格式,解析3,4,6,7个字符的十六进制,和rgb/a完整或部分字符串(百分比定义的rgb/a值除外)没有标志。
(如果支持IE,替换少量的ES6语法)
一句话:
function rgbaHex(c,a,i){return(Array.isArray(c)||(typeof c==='string'&&/,/.test(c)))?((c=(Array.isArray(c)?c:c.replace(/[\sa-z\(\);]+/gi,'').split(',')).map(s=>parseInt(s).toString(16).replace(/^([a-z\d])$/i,'0$1'))),'#'+c[0]+c[1]+c[2]):(c=c.replace(/#/,''),c=c.length%6?c.replace(/(.)(.)(.)/,'$1$1$2$2$3$3'):c,a=parseFloat(a)||null,`rgb${a?'a':''}(${[(i=parseInt(c,16))>>16&255,i>>8&255,i&255,a].join().replace(/,$/,'')})`);}
可读版本:
function rgbaHex(c, a) {
// RGBA to Hex
if (Array.isArray(c) || (typeof c === 'string' && /,/.test(c))) {
c = Array.isArray(c) ? c : c.replace(/[\sa-z\(\);]+/gi, '').split(',');
c = c.map(s => window.parseInt(s).toString(16).replace(/^([a-z\d])$/i, '0$1'));
return '#' + c[0] + c[1] + c[2];
}
// Hex to RGBA
else {
c = c.replace(/#/, '');
c = c.length % 6 ? c.replace(/(.)(.)(.)/, '$1$1$2$2$3$3') : c;
c = window.parseInt(c, 16);
a = window.parseFloat(a) || null;
const r = (c >> 16) & 255;
const g = (c >> 08) & 255;
const b = (c >> 00) & 255;
return `rgb${a ? 'a' : ''}(${[r, g, b, a].join().replace(/,$/,'')})`;
}
}
Usages:
rgbaHex(“# a8f”)
rgbaHex(“# aa88ff”)
rgbaHex(“# A8F”)
rgbaHex(“# AA88FF”)
rgbaHex('#AA88FF', 0.5)
rgbaHex(“# a8f”、“0.85”)
/ /等。
rgbaHex('rgba(170,136,255,0.8);')
rgbaHex('rgba(170,136,255,0.8)')
rgbaHex('rgb(170,136,255)')
rgbaHex('rg170,136,255')
rgbaHex(' 170,136,255 ')
rgbaHex 170,136,255,0.8 ([])
rgbaHex ([170136255])
/ /等。
看起来你在寻找这样的东西:
function hexstr(number) {
var chars = new Array("0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f");
var low = number & 0xf;
var high = (number >> 4) & 0xf;
return "" + chars[high] + chars[low];
}
function rgb2hex(r, g, b) {
return "#" + hexstr(r) + hexstr(g) + hexstr(b);
}
我意识到这个问题有很多答案,但如果你像我一样,你知道你的HEX总是6个字符,带或不带#前缀,那么如果你想做一些快速内联的东西,这可能是最简单的方法。它不关心是否以散列开始。
var hex = "#ffffff";
var rgb = [
parseInt(hex.substr(-6,2),16),
parseInt(hex.substr(-4,2),16),
parseInt(hex.substr(-2),16)
];