convert array with objects to one associative array without foreach - php

Question

I have an array like(result of json_decode):
array(2) {
[0]=>
object(stdClass)#1 (3) {
["key"]=>
string(6) "sample"
["startYear"]=>
string(4) "2000"
["endYear"]=>
string(4) "2015"
}
[1]=>
object(stdClass)#2 (3) {
["key"]=>
string(13) "second_sample"
["startYear"]=>
string(4) "1986"
["endYear"]=>
string(4) "1991"
}
}
I want to convert it to array like:
array(2) {
["sample"]=>
array(2) {
["startYear"]=>
string(4) "2000"
["endYear"]=>
string(4) "2015"
}
["second_sample"]=>
array(2) {
["startYear"]=>
string(4) "1986"
["endYear"]=>
string(4) "1991"
}
}
Is there beauty way to do this (cureently I'm using foreach, but I'm not sure it is a best solution).
Added a code example:
<?php
$str='[{"key":"sample","startYear":"2000","endYear":"2015"},{"key":"second_sample","startYear":"1986","endYear":"1991"}]';
$arr=json_decode($str);
var_dump($arr);
$newArr=array();
foreach ($arr as $value){
$value=(array)$value;
$newArr[array_shift($value)]=$value;
}
var_dump($newArr);

Answer 1

You can use array_reduce
$myArray = array_reduce($initialArray, function ($result, $item) {
$item = (array) $item;
$key = $item['key'];
unset($item['key']);
$result[$key] = $item;
return $result;
}, array());

Answer 2

You can create the desired output without making any iterated function calls by using a technique called "array destructuring" (which is a functionless version of list()). Demo
Language Construct Style:
$result = [];
foreach ($array as $object) {
[
'key' => $key,
'startYear' => $result[$key]['startYear'],
'endYear' => $result[$key]['endYear']
] = (array)$object;
}
var_export($result);
Functional Style:
var_export(
array_reduce(
$array,
function($result, $object) {
[
'key' => $key,
'startYear' => $result[$key]['startYear'],
'endYear' => $result[$key]['endYear']
] = (array)$object;
return $result;
},
[]
)
);
Both will output:
array (
'sample' =>
array (
'startYear' => '2000',
'endYear' => '2015',
),
'second_sample' =>
array (
'startYear' => '1985',
'endYear' => '1991',
),
)

Answer 3

Simply you can use array_map like as
$result = array_map('get_object_vars',$your_array);
Edited:
As after checking your code that you've added an example over here there's no need to use an extra functions or loop to convert your array of objects into associative array instead you simply need to pass second parameter true within json_decode function like as
$arr = json_decode($json,true);
Demo

Answer 4

An alternative to array_reduce and other provided solutions could be:
$list = array_combine(
array_column($list, 'key'),
array_map(fn ($item) => (array) $item, array_values($list))
);
Or:
$list = array_combine(
array_column($list, 'key'),
array_map('get_object_vars', $list)
);