How to get specific array with a specific key/value pair, from a multidimensional array

Question

in PHP if i have a multidimensional array like this how can i get the only the array that has the key highlight = 1, without using foreach, for, or any kind of loop? is it possible?

array(
array(
    [id] => xxx,
    [name] => blah,
    [highlight] => 0

),
array(
    [id] => yyy,
    [name] => blahblah,
    [highlight] => 1
),
array(
    [id] => zzz,
    [name] => blahblahblah,
    [highlight] => 0
),
)

thanks

`json_encode` and then `preg_match_all` <<== worst idea ever — Joel Harkes, May 01 '13 at 11:22
Why are you afraid of loops when almost everything uses loops ?? — Baba, May 01 '13 at 11:34
Try this http://stackoverflow.com/questions/1019076/how-to-search-by-key-value-in-a-multidimensional-array-in-php — Maroun Baydoun, May 01 '13 at 11:35
@Baba im not affraid of loops, just the way that i have my DB, if that is array of photos, and only one with highlight=1, dont want to loop 1000 photos to get one. if is not possible, i prefer to change the DB and do it in another way. Yes we use alot of loops, but is the worst thing u can do, in terms of memory — Pedro Luz, May 01 '13 at 11:48
That is micro optimization ... PHP loops are actually very fast — Baba, May 01 '13 at 11:53

billyonecan · Accepted Answer · 2013-05-01T12:32:45.337

5

Unless I'm mistaken, it's not possible without performing some kind of loop. The best solution I can think of would be to use array_filter(), however, this is essentially the same as looping:

$theArray = array_filter($array, function($v) { return $v['highlight'] == 1; });

edited May 01 '13 at 12:32

answered May 01 '13 at 11:29

billyonecan

20,090
8
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Can you elaborate why you think that the best thing is `array_filter` and not just a loop? – hakre May 01 '13 at 12:28
@hakre I'm lazy and this was the shortest way I could think of doing it. I very much doubt there's any performance benefit to doing this over a regular loop. – billyonecan May 01 '13 at 12:36

Baba · Answer 2 · 2013-05-01T12:00:08.307

You should not be afraid of loops because almost all function you can use in this case use loops (arrap_map,array_reduce,array_walk etc) .... etc.

For the fun of it you can try goto :D

START: // your array
O1: $num = - 1; $found = array(); $total = count($array);
O2: $num ++;
O3: if ($num >= $total) goto O6;
O4: if ($array[$num]['highlight'] == 1) $found[] = $array[$num];
O5: goto O2;
O6: print_r($found);
END:

See live Demo it works

score 1 · Answer 3 · answered May 01 '13 at 11:57

1

You need to key the array differently if you don't want to use a loop but the hashtable PHP offers out of the box for arrays.

answered May 01 '13 at 11:57

hakre

193,403
52
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836

score 1 · Answer 4 · answered Oct 16 '14 at 14:37

$json = (json_encode($array));
if (stripos($json,'"highlight":"1"')){
    echo "exists";
}else{ 
echo "doesn't";
}

Fairly fast, no loops, simple...however, it will only tell you whether what you searched for exists. Can be extended to get id & name and converted back to array.

Hope this helps someone out there.

score 0 · Answer 5 · answered May 01 '13 at 11:39

An alternative to billyonecan's correct answer would be to return an index to your array instead of making a copy of the array, as follows:

<?php

$test = array(
  array(
    'id' => xxx,
    'name' => blah,
    'highlight' => 0

  ),
  array(
    'id' => yyy,
    'name' => blahblah,
    'highlight' => 1
  ),
  array(
    'id' => zzz,
    'name' => blahblahblah,
    'highlight' => 0
  ),
);

$myKey = null;

array_walk($test, function(&$item1, $key) {
  global $myKey;
  if ($item1['highlight'] == 1) {
    $myKey = $key;
  }
});

var_dump($test[$myKey]);
// array(3) { ["id"]=> string(3) "yyy" ["name"]=> string(8) "blahblah" ["highlight"]=> int(1) }

How to get specific array with a specific key/value pair, from a multidimensional array

5 Answers5