Returns a version of str with a backslash character (\) before every character that is among these:
. \ + * ? [ ^ ] ( $ ) |
Megjegyzés: Ez a függvény "binary-safe", azaz helyesen kezeli a 127-es ASCII kód feletti karaktereket is.
See also addslashes(), htmlentities(), htmlspecialchars(), nl2br(), and stripslashes().