Merging 3 arrays to one base on field - php

Question

I have three array (is about the data migration)
$a = Array
(
[0] => Array
(
[0] => province
[1] => 701
[2] => AA
[3] => A
)
..
)
$b = Array
(
[0] => Array
(
[0] => district
[1] => 70101
[2] => BB
[3] => B
)
[1] => Array
(
[0] => district
[1] => 70102
[2] => BB1
[3] => B1
)
..
)
$c = Array
(
[0] => Array
(
[0] => commune
[1] => 7010101
[2] => CC
[3] => C
),
[1] => Array
(
[0] => commune
[1] => 7010102
[2] => CC1
[3] => C1
)
..
)
What I want is to merge all $a , $b , $c' to become a new array
in this example array that have value701is the key of sub array70101and70101is the key of sub array7010101`
So the final array may look something like this:
$d = array (
701=>array(
70101=>array(7010101,7010102),
70102=>array(7010201,7010202),
),
)

Answer 1

The attempt is like the following:
# Your data structure here:
$a = array(
'701' => 'foo',
'702' => 'bar',
);
$b = array(
'70101' => 'foo-foo',
'70102' => 'foo-bar',
);
$c = array(
'7010101' => 'foo-foo-foo',
'7010102' => 'foo-foo-bar',
'7020101' => 'bar-foo-foo',
'7020201' => 'bar-bar-foo',
);
# The array you want
$buffer = array();
# Loop through the deepest elements (here: commune)
foreach ($c as $key => $value) {
# Find the keys for the parent groups
$province_key = substr($key, 0, 3);
$district_key = substr($key, 0, 5);
# Fill the buffer
$buffer[$province_key][$district_key][$key] = $value;
}
# Debug: The generated array
echo '<pre>';
print_r($buffer);
echo '</pre>';
You can copy&paste it here and hit run.

Answer 2

Test data:
$arrayA = [
[
0 => 'province',
1 => 701,
2 => 'AA',
3 => 'A'
],
[
0 => 'province',
1 => 702,
2 => 'AA1',
3 => 'A1'
],
];
$arrayB = [
[
0 => 'district',
1 => 70102,
2 => 'BB',
3 => 'B'
],
[
0 => 'district',
1 => 70101,
2 => 'BB1',
3 => 'B1'
],
];
$arrayC = [
[
0 => 'commune',
1 => 7010101,
2 => 'CC',
3 => 'C'
],
[
0 => 'commune',
1 => 7010102,
2 => 'CC1',
3 => 'C1'
]
];
Solution:
function mergeArraysToOneOnField(array $arrayA, array $arrayB, array $arrayC, $fieldName) {
$result = [];
/*
checks like
!is_string($fieldName) && !is_integer($fieldName)
*/
$arrayARelevantFields = array_column($arrayA, $fieldName);
$arrayBRelevantFields = array_column($arrayB, $fieldName);
$arrayCRelevantFields = array_column($arrayC, $fieldName);
foreach ($arrayARelevantFields as $arrayARelevantField) {
$arrayAFilteredRelevantField = filterArrayByStrpos($arrayBRelevantFields, $arrayARelevantField);
foreach ($arrayAFilteredRelevantField as $arrayBRelevantField) {
$result[$arrayARelevantField][$arrayBRelevantField] =
filterArrayByStrpos($arrayCRelevantFields, $arrayBRelevantField)
;
}
}
return $result;
}
Test run:
$mergedArray = mergeArraysToOneOnField($arrayA, $arrayB, $arrayC, 1);
print_r($mergedArray);
Test Result:
Array
(
[701] => Array
(
[70102] => Array
(
)
[70101] => Array
(
[0] => 7010101
[1] => 7010102
)
)
)
The solution can be extended with recursion, in order to hanlde a variable number of input arrays:
function mergeArraysToOneOnField(array &resultArray, array $inputAarray, $field) {
...
}

Answer 3

$array1 = array("color" => "red", 2, 4);
$array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$result = array_merge($array1, $array2);
Output
Array ( [color] => green [0] => 2 [1] => 4 [2] => a [3] => b [shape] => trapezoid [4] => 4 )