PHP Search multidimensional array for value & get corresponding element value

Question 1

I am using PHP & I have a multi dimensional array which I need to search to see if the value of a "key" exists and if it does then get the value of the "field". Here's my array:

Array
(
    [0] => Array
    (
        [key] => 31
        [field] => CONSTRUCTN
        [value] => LFD_CONSTRUCTION_2
    )
    [1] => Array
    (
        [key] => 32
        [field] => COOLING
        value] => LFD_COOLING_1
    )
)

I want to be able to search the array for the "key" value of 31. If it exists, then I want to be able to extract the corresponding "field" value of "CONSTRUCTN".

I've tried using array_search(31, $myArray) but it does not work...

Question 2

function searchMultiArray($val, $array) {
  foreach ($array as $element) {
    if ($element['key'] == $val) {
      return $element['field'];
    }
  }
  return null;
}

And then:

searchMultiArray(31, $myArray);

Should return "CONSTRUCTN".

Question 3

You need to iterate over your results, adding a new entry to the output when you encounter a new team, or updating the points value when you find the same team again. This is most easily done by initially indexing the output by the team name, and then using array_values to re-index the array numerically:

$teams = array();
foreach ($results as $result) {
    $team = $result['team'];
    if (!isset($teams[$team])) {
        $teams[$team] = array('team' => $team, 'points' => $result['punti']);
    }
    else {
        $teams[$team]['points'] += $result['punti'];
    }
}
$teams = array_values($teams);
print_r($teams);

Output (for your sample data):

Array
(
    [0] => Array
        (
            [team] => Red Bull Racing
            [points] => 418
        )
    [1] => Array
        (
            [team] => Scuderia Ferrari
            [points] => 353
        )
    [2] => Array
        (
            [team] => Mercedes-AMG
            [points] => 516
        )
    [3] => Array
        (
            [team] => Racing Point F1
            [points] => 147
        )
    [4] => Array
        (
            [team] => Haas F1
            [points] => 127
        )
)

Demo on 3v4l.org

Question 4

Nice choice of array_column()! Just extract an array with Country as the key and Out_Count as the value:

$los = 'Belgium';
$result = array_column($outs, 'Out_Count', 'Country')[$los];

To do it your way:

$los = 'Belgium';
$key = array_search($los, array_column($outs, 'Country'));
$result = $outs[$key]['Out_Count'];

Or:

$result = $outs[array_search($los, array_column($outs, 'Country'))]['Out_Count'];

Question 5

As your array is multidimensional - you have to iterate over it to find the value you need:

foreach ($ret as $value) {
    // the index you want to search is always `2`?
    if ($value[2] == 'uspb2') {
        echo $value[0];
        break;
    }
}

And moving to function:

function findMyValue(
    $array, 
    $search_key,
    $search_str, 
    $key
) {
    foreach ($array as $v) {
        if ($v[$search_key] == $search_str) {
            return $v[$key];
        }
    }
    return 'NOT_FOUND';
}

echo findMyValue($ret, 2, 'euro', 1); // outputs 3
echo findMyValue($ret, 2, 'uspb', 0); // outputs 1890

And as already noticed in comments - it's not a poorly formated text, it's JSON. You can get an array from JSON string simply with json_decode function:

$file=file_get_contents("http://www.example.com/feed/");
$ret = json_decode($file, true);
var_dump($ret);

Question 6

You can do it like this, do the calculation from the innermost of the array. Check the demo.

<?php
function f(&$array)
{
    foreach($array as $k => &$v)
    {
        if(is_array($v))
        {
            if(count($v) == count($v, 1))
            {
                unset($array[$k]);
                if($k == 'sum')
                {
                    $v =  array_sum($v);
                    $array[] = $v;

                }elseif($k == 'multiply'){
                    $v = array_product($v);
                    $array[] = $v;
                }else{

                    foreach($v as $vv)
                        $array[] = $vv;
                }
            }else
                f($v);
        }
    }
}

while(count($array) != count($array, 1))
{
    f($array);
}

print_r($array);

Note：

traverse array from outer to inner
traverse array from inner to outer

PHP Search multidimensional array for value & get corresponding element value

Answers

php,arrays,multidimensional-array