Convert delimited keys into new (multi-level) key paths [duplicate] - php

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Convert dot syntax like "this.that.other" to multi-dimensional array in PHP
(10 answers)
Closed 9 months ago.
My question is how correctly convert from one element of array ['a_b_c' => 123] to ['a' => ['b' => ['c' => 123]]]; with any level!
As example input data(in tests), i use
['a_a' => '2', 'a_b' => '333', 'c_c' => '123']
as key separator i choose '_'
And waiting result like:
['a' => ['a' => '2', 'b' => '333'], 'c' => ['c' => '123']
but actual result is:
['a' => ['b' => '333'], 'c' => ['c' => '123']]
i use static function from class Helper:
/**
* #param array|string $data Inserted data, like regular array, or simple string(will return as is)
* #param string $separator string separator to know what we had.
* #return array|string
*/
public static function unFlatArr($data, $separator = '_')
{
$return = [];
if (is_iterable($data)) {
foreach ($data as $oldKey => $value) {
$keysArr = explode($separator, $oldKey, 2);
$key = $keysArr[0];
$k = $keysArr[1] ?? null;
if (null !== $k) {
//got nesting.
$value = self::unFlatAr([$k => $value], $separator);
}
$return[$key] = $value;
}
} else {
$return = $data;
}
return $return;
}
Where i'm fail and why, please, tell me.
thank you.

Answer 1

Solution is to check content of joining, not only is_array() checking.
Converted to simple function(without class/static and etc):
<?php
// worked with any lvl
function unFlatArr($array, $delimiter = '_')
{
$result = [];
foreach ($array as $notations => $value) {
// extract keys
$keys = explode($delimiter, $notations);
// reverse keys for assignments
$keys = array_reverse($keys);
// set initial value
$lastVal = $value;
foreach ($keys as $key) {
// wrap value with key over each iteration
$lastVal = [
$key => $lastVal
];
}
// merge result
$result = array_merge_recursive($result, $lastVal);
}
return $result;
}
$array = ['a_a' => '2', 'a_b' => '33', 'a_b_c' => '444', 'a_b_d' => '555', 'c_c' => '12'];
var_export(unFlatArr($array));
Worked correctly, thanx Ilya, Erkin!
And another solution by mickmackusa
did not work correctly with 2+ level of input array !