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Use JavaScript to Convert RGBA CSS Value to Hexadecimal
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#!/usr/bin/env node | |
// Takes an rgba() CSS value and converts it to its 8 digit hexadecimal value. | |
// | |
// Usage: ./rgbaToHex.js "{YOUR_RGBA_STRING}" | |
// | |
// Example: ./rgbaToHex.js "rgba(197, 200, 198, .2)" => #C5C8C633 | |
function trim (str) { | |
return str.replace(/^\s+|\s+$/gm,''); | |
} | |
function rgbaToHex (rgba) { | |
var inParts = rgba.substring(rgba.indexOf("(")).split(","), | |
r = parseInt(trim(inParts[0].substring(1)), 10), | |
g = parseInt(trim(inParts[1]), 10), | |
b = parseInt(trim(inParts[2]), 10), | |
a = parseFloat(trim(inParts[3].substring(0, inParts[3].length - 1))).toFixed(2); | |
var outParts = [ | |
r.toString(16), | |
g.toString(16), | |
b.toString(16), | |
Math.round(a * 255).toString(16).substring(0, 2) | |
]; | |
// Pad single-digit output values | |
outParts.forEach(function (part, i) { | |
if (part.length === 1) { | |
outParts[i] = '0' + part; | |
} | |
}) | |
return ('#' + outParts.join('')); | |
} | |
if (process.argv.length >= 3) { | |
console.log(rgbaToHex(process.argv[2])); | |
} else { | |
console.log('You must supply an rgba() CSS string to convert. Example: rgba(197, 200, 198, .2)'); | |
console.log(''); | |
console.log('Usage: ./rgbaToHex.js "{YOUR_RGBA_STRING}"'); | |
process.exit(1); | |
} |
This is incorrect for r,g,b,a values which result in a string of length 1 when toString(16) is called on them.
e.g rgba(255, 15, 255, 255) => #fffffff which should actually be #ff0fffff.
To fix this you will need to add a leading 0 to any value r,g,b or a which is length 1.
Thanks!
I have made changes to fix the comments above (I hope).
cc/ @bendaly818, @manuelQuiroz and @knutole
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You have to make a small change in the part of the method substring()
return ('#' + r.toString(16) + g.toString(16) + b.toString(16) + (a * 255).toString(16)).substring(0, 7);