Selecting one row of a multidimensional array under condition?

[frickettz]

Is it possible to select all the values of one particular row IF and only if the room_id key == 3 in the row's nested array?

How could I do that without knowing the parent key for each row?

PHP Code:

Array ( 
[0] => Array ( [room_id] => 3 [room] => Living [affiliate_url] => link3 ) 
[1] => Array ( [room_id] => 1 [room] => Kitchen [affiliate_url] => link1 )
[2] => Array ( [room_id] => 7 [room] => Bed [affiliate_url] => link7 )
) 


[Fou-Lu]

You can yes. There are a number of ways to determine this from filtering to iteration. Given what you have here though, is there a reason that the room_id isn't specified as the index for the outer array instead of as an item within the inner array?
I'd probably use a filter. The filter's only downside is its signature is not changeable, so you have to use global references in order to modify what you are looking for.

PHP Code:

function filterArray($item)
{
    global $iRoomNum;
    $bResult = false;
    $roomID = (int)$iRoomNum;

    if (is_array($item) && isset($item['room_id']) && $item['room_id'] == $roomID)
    {
        $bResult = true;
    }
    return $bResult;
}

$iRoomNum = 3;
$yourArray = Array ( 
    Array ( 'room_id' => 3, 'room' => 'Living', 'affiliate_url' => 'link3' ),
    Array ( 'room_id' => 1, 'room' => 'Kitchen', 'affiliate_url' => 'link1' ),
    Array ( 'room_id' => 7, 'room' => 'Bed', 'affiliate_url' => 'link7' )
) ;
$aFiltered = array_filter($yourArray, 'filterArray');
print_r($aFiltered); 


[gvre]

The best solution is to specify the room_id as the index of the outer array, as Fou-Lu suggested. If this is not possible, the solution depends on the size of the outer array and the uniqueness of the room_id. If the outer array is too big you could use the following function, that returns immediately when room_id matches $roomId.

PHP Code:

function filterArray($array, $roomId)
{
        if (is_array($array))
        {
                foreach($array as $room)
                        if ($room['room_id'] == $roomId)
                                return $room;
        }
        return null;
} 


If the outer array is not big, you could use the Fou-Lu's solution or the following one (php 5.3 or greater is required).

PHP Code:

$roomId = 3;
$aFiltered = array_filter($yourArray, function ($room) use ($roomId) { return $room['room_id'] == $roomId; });
if (isset($aFiltered[0])) 
        $aFiltered = $aFiltered[0];
print_r($aFiltered);