lbry-desktop/ui/util/hex.js
Sean Yesmunt d3a1822f91 cleanup
2021-03-03 12:54:30 -05:00

46 lines
1.2 KiB
JavaScript

// @flow
export function toHex(str: string): string {
const array = Array.from(str);
let result = '';
for (var i = 0; i < array.length; i++) {
const val = array[i];
const utf = toUTF8Array(val)
.map((num) => num.toString(16))
.join('');
result += utf;
}
return result;
}
// https://gist.github.com/joni/3760795
// See comment that fixes an issue in the original gist
function toUTF8Array(str: string): Array<number> {
var utf8 = [];
for (var i = 0; i < str.length; i++) {
var charcode = str.charCodeAt(i);
if (charcode < 0x80) utf8.push(charcode);
else if (charcode < 0x800) {
utf8.push(0xc0 | (charcode >> 6), 0x80 | (charcode & 0x3f));
} else if (charcode < 0xd800 || charcode >= 0xe000) {
utf8.push(0xe0 | (charcode >> 12), 0x80 | ((charcode >> 6) & 0x3f), 0x80 | (charcode & 0x3f));
}
// surrogate pair
else {
i++;
charcode = (((charcode & 0x3ff) << 10) | (str.charCodeAt(i) & 0x3ff)) + 0x010000;
utf8.push(
0xf0 | (charcode >> 18),
0x80 | ((charcode >> 12) & 0x3f),
0x80 | ((charcode >> 6) & 0x3f),
0x80 | (charcode & 0x3f)
);
}
}
return utf8;
}