PHP code to intercept string according to specified length

PHP intercepts the string according to the specified length. If the string exceeds the specified length, it will be replaced with..., but this code does not support the distinction between Chinese and English

//if a string is longer than the defined length,
//it will add 3 periods to the end of the string.
//you can change it to what ever you want for example:
//return substr($str,0, $len).'[Read More]';
//http://www.sharejs.com
function strLength($str,$len){
 $lenght = strlen($str);
 if($lenght > $len){
 return substr($str,0,$len).'...';
 }else{
 return $str;
 }
}
$str = "This is a fairly long string.";
//The fist part is the string, the second part is how long it can be
echo strLength($str,10).'echo strLength($str,30);
?>

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