Regular Expressions, stripping everything but letters, spaces, and digits

[ForgottenCreatur]

How do I go about removing everything in a string besides letters, spaces, and digits?

So far I have

$newvar = ereg_replace("[^A-Za-z0-9]", "", $string);

That takes care of the letters and digits, but not the spaces.

Help?

[best4service]

spaces:
\s //any whitespace spaces, new lines tabs

try that

[ForgottenCreatur]

I have tried things like
$newvar = ereg_replace("[^A-Za-z0-9\s]", "", $string);

but that hasn't worked

[PHP4Living]

try to use trim() to remove spaces

[7stud]

That takes care of the letters and digits, but not the spaces.

1) Why are you using ereg()? Everything I've read says you should use preg() and forget that ereg() even exists.

2) Shortcuts for character classes don't work with ereg(), e.g. \s.

3) A space is represented by? How about......a space!

$regex ="/[^0-9a-zA-Z ]/";
                     ^
$str = "a-A&a 9-8,7*6 b B b";
echo  preg_replace($regex, "", $str);