//If you try to use mb_detect_encoding to detect whether a string is valid UTF-8, use the strict mode, it is pretty worthless otherwise.

​

$str = 'áéóú'; // ISO-8859-1

mb_detect_encoding($str, 'UTF-8'); // 'UTF-8'

mb_detect_encoding($str, 'UTF-8', true); // false

​

//Example if you have a website that uses 2 different encoding and you want your values to be in utf8

$str = (mb_detect_encoding($str, 'UTF-8', true)) ? $str : utf8_encode($str);

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