Matching one array value to another and retrieving/replacing matched - php

Question

I'm trying to retrieve the "location" in $arrayB by using the key "locationid" in $arrayA:
$arrayA=Array
(
(0) => Array
(
(domain) => 'testing.com',
(locationid) => '7',
(description) => 'Lorem'
),
(1) => Array
(
(domain) => 'testing2.com',
(locationid) => '6',
(description) => 'Ipsum'
),
(2) => Array
(
(domain) => 'testing3.com',
(locationid) => '1',
(description) => 'Foo'
)
);
$arrayB=Array
(
(0) => Array
(
(locationid) => '1',
(location) => 'London'
),
(1) => Array
(
(locationid) => '6',
(location) => 'New York'
),
(2) => Array
(
(locationid) => '7',
(location) => 'Tokyo'
)
);
And then ultimately ending up with $arrayC which would be something along the lines of:
$arrayC=Array
(
(0) => Array
(
(domain) => 'testing.com',
(location) => 'Tokyo',
(description) => 'Lorem'
),
etc...
);
What would be the best way to go about this? I guess some sort of "foreach" function but I can't get my head around it!
Many thanks

Answer 1

One nested loop would do-it but I think this is more readable
<?php
$arrayA=Array
(
'0' => Array
(
'domain' => 'testing.com',
'locationid' => '7',
'description' => 'Lorem'
),
'1' => Array
(
'domain' => 'testing2.com',
'locationid' => '6',
'description' => 'Ipsum'
),
'2' => Array
(
'domain' => 'testing3.com',
'locationid' => '1',
'description' => 'Foo'
)
);
$arrayB=Array
(
'0' => Array
(
'locationid' => '1',
'location' => 'London'
),
'1' => Array
(
'locationid' => '6',
'location' => 'New York'
)
);
function getDomain($id, $list) {
foreach ($list as $domain) {
if ($domain['locationid'] == $id) {
return $domain;
}
}
}
$arrayC = array();
foreach ($arrayB as $id) {
$newData = getDomain($id['locationid'], $arrayA);
$newData['location'] = $id['location'];
$arrayC[] = $newData;
}
var_dump($arrayC);

Answer 2

$arrayB = array( 7 => 'Tokyo' );
$arrayC = array_map( function(&$a) use ($arrayB) {
$a['location'] = $arrayB[$a['locationid']];
unset([$a['locationid']);
return $a;
}, $arrayA);
maybe like that.

Answer 3

$arrayA = array(
array('domain' => 'testing.com', 'locationid' => '7', 'description' => 'Lorem'),
array('domain' => 'testing2.com', 'locationid' => '6', 'description' => 'Ipsum'),
array('domain' => 'testing3.com', 'locationid' => '1', 'description' => 'Foo')
);
$arrayB = array(
array('locationid' => '1', 'location' => 'London'),
array('locationid' => '6', 'location' => 'New York'),
array('locationid' => '7', 'location' => 'Tokyo')
);
$arrayA_a = array();
foreach($arrayA AS $arrayA_b)
{
$arrayA_a["$arrayA_b[locationid]"] = $arrayA_b;
}
$arrayB_a = array();
foreach($arrayB AS $arrayB_b)
{
$arrayB_a["$arrayB_b[locationid]"] = $arrayB_b;
}
$arrayC = array();
foreach($arrayA_a AS $arrayA_a_key => $arrayA_a_value)
{
$arrayC["$arrayA_a_key"]['domain'] = $arrayA_a_value['domain'];
$arrayC["$arrayA_a_key"]['description'] = $arrayA_a_value['description'];
$arrayC["$arrayA_a_key"]['location'] = $arrayB_a["$arrayA_a_key"]['location'];
}
print_r($arrayC);
Array
(
[7] => Array
(
[domain] => testing.com
[description] => Lorem
[location] => Tokyo
)
[6] => Array
(
[domain] => testing2.com
[description] => Ipsum
[location] => New York
)
[1] => Array
(
[domain] => testing3.com
[description] => Foo
[location] => London
)
)
If you want to reset the keys of $arrayC:
$arrayC = array_merge($arrayC);
Array
(
[0] => Array
(
[domain] => testing.com
[description] => Lorem
[location] => Tokyo
)
[1] => Array
(
[domain] => testing2.com
[description] => Ipsum
[location] => New York
)
[2] => Array
(
[domain] => testing3.com
[description] => Foo
[location] => London
)
)