Refining my javascript REGEX to format a short-name

I am writing a javascript regex to turn a string into a short-name (for use in clean URLs). I need it to:

• convert it to lowercase
• strip all "bad" characters
• trim all leading and trailing whitespace
• replace single and multiple spaces for a dash.

This is what I have so far (newlines added for readability):

clean_value = $(this).val().toLowerCase().replace(/[^a-z0-9 -]+/g,'')
              .replace(/^\s+|\s+$/g, ''开发者_如何学C).replace(/ +(?= )/g,'-')
              .replace(/ /g, '-');

This does it but I KNOW there is a more efficient way to form these REGEXs... I am so bad with them and have spent an hour trying to figure out how to combine these as much as possible.

Any help would be greatly appreciated!

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This doesn't look too bad in my opinion. Better have a sequence of readable, manageable regexes than one all-purpose monster that nobody (including yourself) will understand a few weeks from now.

One suggestion:

clean_value = $(this).val().toLowerCase().replace(/[^a-z0-9 -]+/g,'')
              .replace(/^\s+|\s+$/g, '').replace(/ +/g,'-');

to make the last replace() do what you specified - convert one or more spaces into a single dash.

If you still have multiple dashes in a row that you want to reduce to a single one, you could add a

.replace(/-{2,}/, '-')

at the end.

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The part where you trim the whitespace is actually faster if you split it into two separate replaces. See: Faster JavaScript Trim. Here's how I would recommend doing it:

function clean(text) {
    return text.replace(/^\s+/,'').replace(/\s\s*$/,'').toLowerCase()
        .replace(/[^a-z0-9\-\s]+/g,'').replace(/\s+/g,'-');
}

Note that the order is important to avoid multiple dashes.