extendHex
Extends a 3-digit color code to a 6-digit color code.
Use Array.prototype.map()
, String.prototype.split()
and Array.prototype.join()
to join the mapped array for converting a 3-digit RGB notated hexadecimal color-code to the 6-digit form.
Array.prototype.slice()
is used to remove #
from string start since it's added once.
const extendHex = (shortHex) =>
"#" +
shortHex
.slice(shortHex.startsWith("#") ? 1 : 0)
.split("")
.map((x) => x + x)
.join("");
extendHex("#03f"); // '#0033ff'
extendHex("05a"); // '#0055aa'