Php order multidimensional array by first key external value - php

Question

I need to reorder multidimensional array by Region Name.
But my multiarray is actually indexed by REGION_ID (first key) for semplicity like:
$array = array(
1 => array( // 1 is REGION_ID
"Value" => "Val-1",
"Children" => array(
...
)
),
2 => array( // 2 is REGION_ID
"Value" => "Val-2",
"Children" => array(
...
)
),
3 => array( // 3 is REGION_ID
"Value" => "Val-3",
"Children" => array(
...
)
),
4 => array( // 4 is REGION_ID
"Value" => "Val-4",
"Children" => array(
...
)
),
...
);
foreach ( $array as $region_id => $sub_array ) {
var_dump($region_id);
}
Where my table REGION is:
ID | Name
--------------
1 | Emilia
--------------
2 | Calabria
--------------
3 | Veneto
--------------
4 | Puglia
--------------
...
I'd like, so, to reorder my $array by Name of my table:
Calabria, then, Emilia, Puglia, Veneto... so my $array has to be:
$array = array(
2 => array(
"Value" => "Val-2",
"Children" => array(
...
)
),
1 => array(
"Value" => "Val-1",
"Children" => array(
...
)
),
4 => array(
"Value" => "Val-4",
"Children" => array(
...
)
),
3 => array(
"Value" => "Val-3",
"Children" => array(
...
)
),
...
);
I don't know how to sort using my logic...

Answer 1

assign the correct sorted array from database to $sorting
$sorting = ...[some function to retrive a sorted array from the database in the desired order]
for example "SELECT * FROM REGION ORDER BY Name"
ERRATA:
if you can't add the "ORDER BY" to sql query, just get the values and use usort (http://php.net/manual/en/function.usort.php) function to have the $sorting array in the correct order.
so, you should have something like (eqivalent):
$sorting = [
['ID' => 2, 'Name' => 'Calabria'],
['ID' => 1, 'Name' => 'Emilia'],
['ID' => 4, 'Name' => 'Puglia'],
['ID' => 3, 'Name' => 'Veneto']
];
or var_dump($sorting)
array (size=4)
0 =>
array (size=2)
'ID' => int 2
'Name' => string 'Calabria' (length=8)
1 =>
array (size=2)
'ID' => int 1
'Name' => string 'Emilia' (length=6)
2 =>
array (size=2)
'ID' => int 4
'Name' => string 'Puglia' (length=6)
3 =>
array (size=2)
'ID' => int 3
'Name' => string 'Veneto' (length=6)
now run the following loop:
$sorted_array = [];
foreach ($sorting as $sort_element) {
$sorted_array[] = $array[$sort_element['ID']];
}
the $sorted_array will have the required sort order
array (size=4)
0 =>
array (size=2)
'Value' => string 'Val-2' (length=5)
'Children' => ...
1 =>
array (size=2)
'Value' => string 'Val-1' (length=5)
'Children' => ...
2 =>
array (size=2)
'Value' => string 'Val-4' (length=5)
'Children' => ...
3 =>
array (size=2)
'Value' => string 'Val-3' (length=5)
'Children' => ...

Answer 2

<?php
$array = array(
1 => array(
"Value" => "Val-1",
"Children" => array(
)
),
2 => array(
"Value" => "Val-2",
"Children" => array(
)
),
3 => array(
"Value" => "Val-3",
"Children" => array(
)
),
4 => array(
"Value" => "Val-4",
"Children" => array(
)
),
);
$region = array(1 => 'Emilia', 2 => 'Calabria', 3 => 'Veneto', 4 => 'Puglia');
asort($region);
$new_array = [];
foreach ($region as $key => $value) {
$new_array[ $key ] = $array[ $key ];
}
print_r($new_array);
You can see this working here : http://tpcg.io/K23FfH