Compare keys in arrays and make new array with comparison values - php

Question

I have 2 arrays that I need to compare and then create a new array with the key staying the same, but adding a new array of as value with the two values from the two arrays.
$array1 = (['SE'] => (string) '123', ['DE'] => (string) '456', ['DK'] => (string) '678');
$array2 = (['SE'] => (string) '999', ['DE'] => (string) '888', ['US'] => (string) '777');
So what I want to achieve is to get the value from both arrays where the key is equal to one another.
I then need to echo it in a similar fashion;
echo '<table>';
foreach($newCompparedArray as $k => $v){
echo '<tr>';
echo '<td>'.$k.'</td><td>'.$v->value1.'</td><td>'.$v->value2.'</td>';
echo '</tr>';
}
echo '</table>';
Another thing is I need the key to only get the values if the key was present in the initial array (i.e. if a key isn't in array1 but is present in array2, don't add this key or it's values to the new array).

Answer 1

This should give you what you want:
$array1 = array('SE' => '123', 'DE' => '456', 'DK' => '678');
$array2 = array('SE' => '999', 'DE' => '888', 'US' => '777');
$keysInBothArrays = array_intersect(array_keys($array1),array_keys($array2));
$newCompparedArray = array();
foreach ($keysInBothArrays as $key) {
$newCompparedArray[$key] = array($array1[$key],$array2[$key]);
}
// print_r($newCompparedArray); exit;
echo '<table>';
foreach($newCompparedArray as $k => $v){
echo '<tr>';
echo '<td>'.$k.'</td><td>'.$v[0].'</td><td>'.$v[1].'</td>';
echo '</tr>';
}
echo '</table>';
The trick is to get the keys which are in both arrays first.

Answer 2

Assuming I understood the output you wanted as
Array(
[SE] => Array ( [0] => 123, [1] => 999 )
[DE] => Array ( [0] => 456, [1] => 888 )
[DK] => Array ( [0] => 678 )
[US] => Array ( [0] => 777 )
)
I would use this code
$array1 =array ('SE' => '123', 'DE' => '456', 'DK' => '678');
$array2 =array ('SE' => '999', 'DE' => '888', 'US' => '777');
$t =array ();
foreach ( $array1 as $key => $value )
$t [$key] =array ($value);
foreach ( $array2 as $key => $value ) {
if ( !isset ($t [$key]) )
$t [$key] =array ($value);
else
$t [$key] [] =$value;
}
//print_r ($t);
foreach ( $t as $key => $value ) {
echo '<tr>';
echo "<td>$key</td><td>" . implode ("</td><td>", $value) . '</td>';
echo "</tr>\n";
}

Answer 3

Loop the first array, check for the value in the second array and if it exists add both:
foreach($array1 as $k => $v) {
$newCompparedArray[$k] = isset($array2[$k]) ? array($v, $array2[$k]) : $v;
}
Then your display loop would be:
foreach($newCompparedArray as $k => $v) {
echo '<td>'.$k.'</td><td>'.$v[0].'</td><td>'.$v[1].'</td>';
}
Obviously in the first loop if you define array('value1'=>$v, 'value2'=>$array2[$k]) then you could use $v['value1] and $v['value2'].
The shorter version:
$newCompparedArray = array_intersect_key(array_merge_recursive($array1, $array2), $array1);