preg_replace in my PHP script doesn't work

I've a user form where I take a phone number as input in one of 开发者_StackOverflow社区my fields. I have two seperate RegEx statements checking on the input.

First one is:

preg_match('/^([\(]{1}[0-9]{3}[\)]{1}[\.| |\-]{0,1}|^[0-9]{3}[\.|\-| ]?)?[0-9]{3}(\.|\-| )?[0-9]{4}$/', $phone);

and it works great. It can identify many different formats i.e. 222-333-4444 or 2224445555.

On the other hand when I try:

preg_replace('/\+?1?[-\s.]?\(?(\d{3})\)?[-\s.]?(\d{3})[-\s.]?(\d{4})/g', '($1) $2-$3', $phone);

which is supposed to format incoming string into (222) 333-4444 format, $phone is unchanged after the preg_replace() call.

Any help will be much appreciated!

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Just to make sure: You need to catch the return value, preg_replace doesn't modify the parameters directly:

$phone = preg_replace(..., $phone);

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Simplified the above, and came up with the following:

preg_replace( '/\b(\d{3})\D?(\d{3})\D?(\d{4})\b/' , '($1) $2-$3' , $inString );

Testing results:

preg_replace( '/\b(\d{3})\D?(\d{3})\D?(\d{4})\b/' , '($1) $2-$3' , '222-333-4444' );
# Returns '(222) 333-4444'

preg_replace( '/\b(\d{3})\D?(\d{3})\D?(\d{4})\b/' , '($1) $2-$3' , '2223334444' );
# Returns '(222) 333-4444'

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It was the /g causing the error in the pattern. Once I removed that it worked. Thanks everyone for trying!