如何只获取数组中第一个匹配的值

Question

Edit: I meant to ask what is the best/fastest way to get the first match or the first xx matches.

I have an array

$arr = ('abc', 'ded', 'kjld', 'abr', 'cdfd');

I want to shuffle this array first, and then retrieve ONLY the first value that matches the pattern /ab/. So, the returned value could be abc or abr.

I looked at preg_grep, but it will return an array of all the matches. Of course I could just retrieve the first value of the resultant array, but that is wasteful and requires an extra step of array manipulation. Is there another function or a preg_grep switch that specifies return only the first matched value (or first 5 matched values). I have looked at preg_match and preg_search, but they don't seem to give what I want.

Answer 1

You can loop through your array and end the loop when you find a match using break:

foreach($arr as $value) {
    if(preg_match($pattern,$value)) {
        $return_string=$value;
        break;
    }
}

To specify a limit:

$limit=3;
$i=0 // sets the number of returned results to 0
$results=array();
foreach($arr as $value) {
    if(preg_match($pattern,$value)) {
        // add the result into the array and increment the counter
        array_push($results,$value);
        $i++;
    } if ($i=$limit) break;
}

You can then use another foreach loop to return your values like:

if(count($results)>0)
foreach ($results as $result) {
    echo $result;
} else echo "No results found";