Convert UTF8 characters to ISO-8859-1 Latin1 and back in PHP

How I converted ISO-8859-1 Latin1 to UTF8

I converted the my file using this PHP function

mb_convert_encoding($file, 'UTF-8', 'ISO-8859-1');

Stack Overflow provided some help to convert UTF8 characters to ISO-8859-1 Latin1 and back in PHP

Have a look at iconv() or mb_convert_encoding(). Just by the way: why don't utf8_encode() and utf8_decode() work for you?

utf8_decode — Converts a string with ISO-8859-1 characters encoded with UTF-8 to single-byte ISO-8859-1

utf8_encode — Encodes an ISO-8859-1 string to UTF-8

So essentially

$utf8 = 'ÄÖÜ'; // file must be UTF-8 encoded
$iso88591_1 = utf8_decode($utf8);
$iso88591_2 = iconv('UTF-8', 'ISO-8859-1', $utf8);
$iso88591_2 = mb_convert_encoding($utf8, 'ISO-8859-1', 'UTF-8');

$iso88591 = 'ÄÖÜ'; // file must be ISO-8859-1 encoded
$utf8_1 = utf8_encode($iso88591);
$utf8_2 = iconv('ISO-8859-1', 'UTF-8', $iso88591);
$utf8_2 = mb_convert_encoding($iso88591, 'UTF-8', 'ISO-8859-1');

all should do the same - with utf8_en/decode() requiring no special extension, mb_convert_encoding() requiring ext/mbstring and iconv() requiring ext/iconv.

Source: https://stackoverflow.com/questions/374425/convert-utf8-characters-to-iso-88591-and-back-in-php