preg_replace

[tonymc]

I am a novice and am really struglling trying to come up with an expression that will locate 4 numbers adjacent to each other. For instance, given the following:

Jan. 1, 1980 -- December 31, 2002

I'd like to remove everything except the four digit years. Ultimately, I'd like to trun this string into:

19802002

I've tried the following:

preg_replace("/[^0-9]{4}/", "", $string);

It's not working as I'd expect it to.... Can somebody please get me started in the right direction?

[NogDog]

$newString = preg_replace('/^.*(\d{4}).*(\d{4}).*$/', "$1$2", $string);

[tonymc]

NogDog wrote:

$newString = preg_replace('/^.*(\d{4}).*(\d{4}).*$/', "$1$2", $string);

Thanks NogDog. That looks good. But in addition to the example I used in my original post:

Jan. 1, 1980 -- December 31, 2002

There may be instances wherein only a single 4 digit year appears. For instance:

May 20, 2001

I'm not sure how to alter the code you gave me to account for this.

[NogDog]

preg_match_all('/\b\d{4}\b/', $string, $matches);
$newString = implode('', $matches[0]);