PHP remove special character from string

I have problems with removing special characters. I want to remove all special characters except "( ) / . % - &", because I'm setting that string as a title.

I edited code from the original (look below):

preg_replace('/[^a-zA-Z0-9_ -%][().][\/]/s', '', $String);

But this is not working to remove special characters like: "’s, "“", "â€", among others.

original code: (this works but it removes these characters: "( ) / . % - &")

preg_replace('/[^a-zA-Z0-9_ -]/s', '', $String);

Solution 1:

Your dot is matching all characters. Escape it (and the other special characters), like this:

preg_replace('/[^a-zA-Z0-9_ %\[\]\.\(\)%&-]/s', '', $String);

Solution 2:

preg_replace('#[^\w()/.%\-&]#',"",$string);

Solution 3:

You want str replace, because performance-wise it's much cheaper and still fits your needs!

$title = str_replace( array( '\'', '"', ',' , ';', '<', '>' ), ' ', $rawtitle);

(Unless this is all about security and sql injection, in that case, I'd rather to go with a POSITIVE list of ALLOWED characters... even better, stick with tested, proven routines.)

Btw, since the OP talked about title-setting: I wouldn't replace special chars with nothing, but with a space. A superficious space is less of a problem than two words glued together...

Solution 4:

Good try! I think you just have to make a few small changes:

• Escape the square brackets ([ and ]) inside the character class (which are also indicated by [ and ])
• Escape the escape character (\) itself
• Plus there's a quirk where - is special: if it's between two characters, it means a range, but if it's at the beginning or the end, it means the literal - character.

You'll want something like this:

preg_replace('/[^a-zA-Z0-9_%\[().\]\\/-]/s', '', $String);

See http://docs.activestate.com/activeperl/5.10/lib/pods/perlrecharclass.html#special_characters_inside_a_bracketed_character_class if you want to read up further on this topic.