php - convert unicode to html entities hex

Question

How to convert a Unicode string to HTML entities? (HEX not decimal)

For example, convert Fran?ais to Français.

Answer 1

For the missing hex-encoding in the related question:

$output = preg_replace_callback('/[x{80}-x{10FFFF}]/u', function ($match) {
    list($utf8) = $match;
    $binary = mb_convert_encoding($utf8, 'UTF-32BE', 'UTF-8');
    $entity = vsprintf('&#x%X;', unpack('N', $binary));
    return $entity;
}, $input);

This is similar to @Baba's answer using UTF-32BE and then unpack and vsprintf for the formatting needs.

If you prefer iconv over mb_convert_encoding, it's similar:

$output = preg_replace_callback('/[x{80}-x{10FFFF}]/u', function ($match) {
    list($utf8) = $match;
    $binary = iconv('UTF-8', 'UTF-32BE', $utf8);
    $entity = vsprintf('&#x%X;', unpack('N', $binary));
    return $entity;
}, $input);

I find this string manipulation a bit more clear then in Get hexcode of html entities.