Merge two Arrays by Values - php

Question

I have this Array:
$mergedItems = array(
0 => array(
'id_item' => 'AZ-110'
'amount' => 12
),
1 => array(
'id_item' => 'BZ-110',
'amount' => 13
),
2 => array(
'id_item' => 'BZ-210',
'amount' => 28
),
3 => array(
'id_item' => 'CZ-291',
'amount' => 11
)
);
AND this Array:
$items = array(
0 => array(
'number' => 'AZ-110'
),
1 => array(
'number' => 'BZ-110'
),
2 => array(
'number' => 'CZ-291'
),
3 => array(
'number' => 'BZ-210'
)
);
Now what i want is to order the first array by the id_item Value to match the same order than the 2nd one by its values.
The resulting array has to include all values of the 2nd array AND the belonging amount-value of the first array. The Keys must not be kept!
I can't use array_merge since the 2nd Array has a dynamic amount of more items, so i only want all items from the second Array that are set in the first one.
Does anyone get what i mean? I am searching for a quick and non-dirty way to get this result as expected.
/Edit:
Expected Array:
$detailedItems = array(
0 => array(
'number' => 'AZ-110',
'amount' => 12
),
1 => array(
'number' => 'BZ-110',
'amount' => 13
),
2 => array(
'number' => 'CZ-291',
'amount' => 11
),
3 => array(
'number' => 'BZ-210',
'amount' => 28
)
);

Answer 1

A PHP 5.5 solution:
$itemMap = array_flip(array_column($mergedItems, 'id_item'));
$result = array_map(
function($i) use($itemMap, $mergedItems) {
return $mergedItems[$itemMap[$i['number']]];
},
$items);
print_r($result);
For 5.3 <= PHP < 5.5 you can simply substitute array_map for array_column:
$itemMap = array_flip(array_map(
function($i) { return $i['id_item']; },
$mergedItems));
How it works
The idea is to create a map of item numbers to indexes inside $mergedItems, ie.
[
'AZ-100' => 0,
'BZ-110' => 1,
'BZ-210' => 2,
// etc
]
With this information at hand it's very easy to iterate over $items (so that the result will be ordered based on that array) and pick the appropriate element from $mergedItems to append to the result each time.

Answer 2

$temp = $items;
foreach($temp as &$val)
{
foreach($mergedItems as $item)
{
if($item['id_item'] == $val['number'])
{
$val['amount'] = $item['amount'];
break;
}
}
}
print_r($temp);

Answer 3

There isn't really a "non-dirty" (meaning single line) way to do this as far as I know, but this function should work:
$out = array();
foreach ($mergedItems as $key => $value) {
if (array_key_exists($key, $detailedItems)) { // Make sure it exists to prevent errors
$out[$key] = $detailedItems[$key] + array('amount' => $value['amount']);
} else {
$out[$key] = $value['amount'];
}
}
print_r($out);

Answer 4

You can try following codes:
foreach ($mergedItems as $item) {
$merged[$item['id_item']] = array('amount' => $item['amount']);
}
foreach ($items as $item)
{
$detailedItems[] = array_merge($item, $merged[$item['number']]);
}
Output
var_dump($detailedItems);
array (size=4)
0 =>
array (size=2)
'number' => string 'AZ-110' (length=6)
'amount' => int 12
1 =>
array (size=2)
'number' => string 'BZ-110' (length=6)
'amount' => int 13
2 =>
array (size=2)
'number' => string 'CZ-291' (length=6)
'amount' => int 11
3 =>
array (size=2)
'number' => string 'BZ-210' (length=6)
'amount' => int 28