$string=preg_replace("/&#([0-9]+);/e","unicodetoiso88591('\\1')",$string);
// $string=preg_replace("/&#[xX]([0-9A-F]+);/e","unicodetoiso88591(hexdec('\\1'))",$string);
$string=preg_replace("/&#([0-9]+);/e","unicodetoiso88591('\\1')",$string);
// $string=preg_replace("/&#[xX]([0-9A-F]+);/e","unicodetoiso88591(hexdec('\\1'))",$string);