preg_replace [expression] issue

[yanisdon]

Hi,

I need some help with this replace function:

 

Here is what I can come up with. This function looks up a string and will replace

any of these characters with a space:

 

$,@#~`%*^&()+=[-][}{;:'"<>?|\!.

 

 

The expression for that works fine:

$expression =  "/\W{3,}|\\\{1,}/";

 

My problem now is, that I want to allow &

What do I have to change?

 

Cheers

Jan

 

 

The function:

    // bad characters  $,@#~`%*^&()+=[-][}{;:'"<>?|\!.

function nspecial($s){

        $expression =  "/\W{3,}|\\\{1,}/";

        $s = preg_replace($expression, " ", $s);

        //now replace appostroph with a character of choice

        $s = preg_replace("/\'{1,}|\"{1,}/","`",$s);

        //$s = addbackslashes($s);

        return $s;

}

[fert]

just remove the &

[yanisdon]

just remove the &

 

// bad characters  $,@#~`%*^&()+=[-][}{;:'"<>?|\!.

 

Thats only a comment.

 

My expression ist this:

$expression =  "/\W{3,}|\\\{1,}/";

 

How can I remove the & here?

 

Cheers

Jan

[effigy]

\W is short for [^A-Za-z0-9_]. You can expand it to that character class, adding the &.

[yanisdon]

Thank you.

So you reckon it's actually a good idea to use

[^A-Za-z0-9_] instead of \W ?

 

Mind you, I want to allow the &

and with \W will match all special chars.

 

So yes, I could use [^A-Za-z0-9_] as it is and therefore & wouldn't match (Wich is exactly what I was looking for), but I was looking for a more slick way to utilise that \W expression with an exception ????

 

Any Ideas?

 

Cheers

Jan

 

 

[effigy]

So you reckon it's actually a good idea to use

[^A-Za-z0-9_] instead of \W ?

 

No. What I meant was \W = [^A-Za-z0-9_]; therefore, if you want to allow ampersands use \W's expansion and add the &: [^A-Za-z0-9_&].

[yanisdon]

Well, thank you.

 

Sorry I didn't get it. That'll do.

 

[^A-Za-z0-9_&]

 

What if I also would like to allow /  ?

 

Do I have to escape that because

 

[^A-Za-z0-9_&/]

 

doesn't seems to be working?

 

Cheers

Jan

[effigy]

You cannot use your delimiter within the pattern without escaping it. See this post.