Question

I have website that’s in win-1251 encoding and it needs to stay that way. But I also need to be able to echo few links that contain non latin, non cyrillic characters like šžāņūī…

I need a function that convert this

"māja un man tā patīk"

to

"māja un man tā patīk"

and that does not touch html, so if there is <b> it needs to stay as <b>, not > or <

And please no advices about the encoding and how wrong that is.

Answer 1

$str = "<b>Obāchan</b> おばあちゃん";

$str = preg_replace_callback('/./u', function ($matches) {
    $chr = $matches[0];
    if (strlen($chr) > 1) {
        $chr = mb_convert_encoding($chr, 'HTML-ENTITIES', 'UTF-8');
    }
    return $chr;
}, $str);

This expects the original $str to be UTF-8 encoded, i.e. your PHP file should be saved in UTF-8. It encodes all non-ASCII compatible code points to HTML entities. Since all HTML special characters are ASCII characters, they remain untouched. The resulting string is pure ASCII. Since the lower Win-1251 code points are ASCII compatible, the resulting string is also a valid Win-1251 string. The above $str converts to:

<b>Ob&#257;chan</b> &#12362;&#12400;&#12354;&#12385;&#12419;&#12435;