PHP - How can I find out if a value exists in an array when compared?

Question

I have an array that looks like this:

Array
(
    [0] => Array
        (
            [0] => 1
            [id] => 1
        )

    [1] => Array
        (
            [0] => 2
            [id] => 2
        )
)

What I would like to do is compare an int value against what's in the id value field. So, if I were to pass in say a 1, I'd like to be able to have a function compare this. I was thinking in_array but I can't get that to work. Does anyone know what function I can use for this?

Thanks.

Answer 1

Try something like this:

$needle = 1;
$found = false;
foreach ($array as $key => $val) {
    if ($val['id'] === 1) {
        $found = $key;
        break;
    }
}
if ($found !== false) {
    echo 'found in $array['.$found.']';
}

---

Since you want something more compact:

$needle = 1;
array_filter($array, create_function('$val', 'return $val["id"] !== '.var_export($needle, true).';'))

That will filter out all those elements that’s id value is not 1.

Answer 2

It's not entirely clear what you'd like the result of the function to be, however I'm guessing you'd like the key of array that contains the ID you are looking for, in that case the following function would find that.

<?php
function get_key($array, $id) {
  foreach ($array as $key => $unit) {
   if ($unit['id'] == $id) {
     return $key;
   }
  }
}