Question

I’ve got a string:

$string = "Hello World!";

I want to turn it into a URL friendly tag, and I’ve developed a function to do it:

function stripJunk($string){
    $string = str_replace(" ", "-", $string);
    $string = preg_replace("/[^a-zA-Z]\s/", "", $string);
    $string = strtolower($string);
    return $string;
}

However, when I run my $string through it above, I get the following:

$string = "hello-world!";

It seems that there are characters slipping through my preg_replace, even though from what I understand, they shouldn’t be.

It should read like this:

$string = "hello-world";

What’s going on here? (This should be easy peasy lemon squeasy!)

Edit 1: I wasn’t aware that regular expressions were beginners stuff, but whatever. Additionally, removing the \s in my string does not produce the desired result.

The desired result is:

1. All spaces are converted to dashes.
2. All remaining characters that are not A-Z or 0-9 are removed.
3. The string is then converted to lower case.

Edit 2+: Cleaned up my code just a little.

Answer 1

The following works just fine to me:

function stripJunk($string){
    $string = str_replace(" ", "-", trim($string));
    $string = preg_replace("/[^a-zA-Z0-9-]/", "", $string);
    $string = strtolower($string);
    return $string;
}