How to move array in multidimensional array using key value? - php

Question

How to move array in multidimensional aray with key value?
I'm using array_push to add values to a multidimensional array. i have an array
$myArray = Array(Array('code' => '1','room' => Array('name' => 'Room-A')),Array('code' =>'1','room' => Array('name' => 'Room-B'
)), Array('code' => '2','room' => Array('name' => 'Vip-1')),Array('code' => '2','room' => Array('name' => 'Vip-2')));
i tried using code like this:
for ($i=0; $i <count($myArray) ; $i++) {
if ($myArray[$i]['code']=='1') {
array_push($myArray[$i]['room'], $myArray[$i]['room']);
}
else{
array_push($myArray[$i]['room'], $myArray[$i]['room']);
}
}
i want the result like this :
Array
(
[0] => Array
(
[code] => 1
[room] => Array
(
[0] => Array
(
[name] => Room-A
)
[1] => Array
(
[name] => Room-B
)
)
)
[1] => Array
(
[code] => 2
[room] => Array
(
[0] => Array
(
[name] => Vip-1
)
[1] => Array
(
[name] => Vip-2
)
)
)
)
Any idea how to join this array?

Answer 1

You can use array_reduce to summarize the array into an associative array using the code as the key. Use array_values to convert the associative array into a simple array.
$myArray = ....
$result = array_values(array_reduce($myArray, function($c, $v){
if ( !isset( $c[ $v['code'] ] ) ) $c[ $v['code'] ] = array( 'code' => $v['code'], 'room' => array() );
$c[ $v['code'] ]['room'][] = $v['room'];
return $c;
},array()));
echo "<pre>";
print_r( $result );
echo "</pre>";
This will result to:
Array
(
[0] => Array
(
[code] => 1
[room] => Array
(
[0] => Array
(
[name] => Room-A
)
[1] => Array
(
[name] => Room-B
)
)
)
[1] => Array
(
[code] => 2
[room] => Array
(
[0] => Array
(
[name] => Vip-1
)
[1] => Array
(
[name] => Vip-2
)
)
)
)

Answer 2

This is the foreach() equivalent of Eddie's answer (I find it easier to read/maintain).
Code: (Demo)
$myArray = [
['code' => '1', 'room' => ['name' => 'Room-A']],
['code' => '1', 'room' => ['name' => 'Room-B']],
['code' => '2', 'room' => ['name' => 'Vip-1']],
['code' => '2', 'room' => ['name' => 'Vip-2']]
];
foreach ($myArray as $row) {
if (!isset($result[$row['code']])) {
$result[$row['code']] = ['code' => $row['code'], 'room' => [$row['room']]];
// ^------------^-- pushed deeper
} else {
$result[$row['code']]['room'][] = $row['room'];
// ^^-- pushed deeper
}
}
var_export(array_values($result));
This question is very similar to many pre-existing questions that want to group by a particular column. I was not able to find an exact duplicate to close with because the requirement of this question is to created a deeper structure to contain the room sub arrays.
Typically I would write:
if (!isset($result[$row['code']])) {
$result[$row['code']] = $row;
to cut down on syntax, but the new output structure must be applied to both the if and the else.
To avoid key duplication/collision, the room subarrays need to be pushed/indexed to a lower level.
In the end, the technique has been demonstrated here many, many times on StackOverflow. You target an element value to group by and use that value as the temporary key as you iterate the input array. Checking if the temporary keys exist or not is the fastest way to determine if a group is new or previously encountered. When you are done, call array_values() to remove the temporary keys (re-index the array).