如何从中过滤不可识别的字符？

Question

I have asked this before but cant find a response/answer to the same.

I do have tags like this..

news,门户,æ–°é—»,portal,网易,163,china,门户ç

I need to extract only news,portal,163,china from above. how can I do it in php??

Answer 1

Assuming you want to keep only ascii alpha-numeric parts of this string, the following code will work:

$str = explode(',', $str);
$str = preg_grep('#^[[:alnum:]]+$#', $str);
$str = implode(',', $str);

This one too:

$str = preg_replace('#(^([^[:alnum:],]+,)+|,[^[:alnum:],]+)#', '', $str);

Which both return news,portal,163,china