Regular Expressions: Preserves only Chinese characters and letters in a string

Regular Expressions: Preserves only Chinese characters and letters in a string
Regular Expressions: Preserves only Chinese characters and letters in a string

------Solution--------------------
Requires Unicode
Preg_replace (' #[^a-z\u4e00-\u9fbb] #i ', ', $string)

It is more complicated to separate full-angle symbols and Chinese characters under GBK.
------Solution--------------------
Transcoding is not required for UTF-8 encoding

$s = ' #$%^4sdfg3 haha sdfgfdg$@#%@#$%as
 
 
  
  ><,.~!tt method ';
  
  
echo preg_replace ('/[\d\w_]/u ', ', $s);
 
 

SDFG haha Sdfgfdgashtt method

Your add-on is not the same as the demand for original posts.

echo preg_replace ('/[\d\w_a-z]/iu ', ', $s);

Haha method

