How to get the length of Chinese string in php

$str = 'Hello world!';
echo strlen($str); // Output 12
?>

However, it comes with PHP In the function, strlen and mb_strlen both calculate the length by calculating the number of bytes occupied by the string. Under different encoding conditions, the number of bytes occupied by Chinese is different. Under GBK/GB2312, Chinese characters occupy 2 bytes, while under UTF-8, Chinese characters occupy 3 bytes.

$str = 'Hello world! ';
echo strlen($str); // Output 12 under GBK or GB2312, 18 under UTF-8
?>

And we often need to judge when judging the length of a string It is the number of characters, not the number of bytes occupied by the string, such as this php code under UTF-8:

$name = 'Zhang Gengchang';
$len = strlen($name);
// Output FALSE, because three Chinese characters occupy 9 bytes under UTF-8
 if($len >= 3 && $len <= 8){
 echo 'TRUE';
}else{
 echo 'FALSE';
}
?>

So there is What convenient and practical method can be used to obtain the length of a string containing Chinese characters? You can use regular rules to calculate the number of Chinese characters, divide by 2 under GBK/GB2312 encoding, divide by 3 under UTF-8 encoding, and finally add the length of the non-Chinese string, but this is too troublesome, WordPress There is a more beautiful piece of code in , which is as follows:

$str = 'Hello, world! ';
preg_match_all('/./us', $str, $match);
echo count($match[0]); // Output 9
?>

Use regular expressions The formula splits the string into single characters, and directly uses count to calculate the number of matching characters, and then we get the result we want.