PHP - Remove all characters from string except listed characters and line returns-CodePudding

I have a php input filter that cleans all unwanted characters from a string. This:

$clean = preg_replace("/[^a-z0-9 \.\-\"_',]/i", "", $string);

This works fine, but I also what to preserve all character returns in the string. I've tried different things like adding '\n\r' or '\R' or '\n\r' to the list of characters in the brackets or adding '/m' to the flag. I'm just not finding the right combo. Any suggestions?

CodePudding user response：

You can use a character class to match any non-printable characters:

$clean = preg_replace("/[^a-z0-9 \.\-\"_',\p{C}]/i", "", $string);

CodePudding user response：

You can use

$clean = preg_replace("/[^a-z0-9 .\"_',\r\n-]/i", "", $string);

Note

The added \r\n
The dot does not have to be escaped inside a character class
The - char is put to the end of the character class and it does not have to be escaped there.