Get value from multiple dimension associative array in Php - php

Question

I have a POST request array that looks like this
$request = array (size=2)
'licence' => string 'uDyQwFwqV7aQG2z' (length=15)
'user' =>
array (size=7)
'first_name' => string 'Danut' (length=5)
'last_name' => string 'Florian' (length=7)
'username' => string 'daniesy9' (length=8)
'password' => string '123456' (length=6)
'rpassword' => string '123456' (length=6)
'email' => string 'daniesy+1#me.com' (length=16)
'phone' => string '9903131' (length=7)
This in fact is an array which represents values sent by a form. I know the name of the elements, for example the username input has the name of user[username] and i have to find the related value from the array, by name. Something like:
$key = "user[username]";
$request[key];
Any idea how to do this?
I know that the correct way to do it is $request["user"]["username"] but it's quite complicated because i have to use the fields names from the form which are user[username], user[firstname], etc and it might have up to 4 levels of depth.

Answer 1

Answered in comments but similar Question to
Convert a String to Variable
eval('$username = $request["user"]["username"];');
Edit
Eval not a valid suggestion as request data.
So I would suggest the second method on this post
<?php
$request = array(
'user' => array(
'username' => 'joe_blogs'
)
);
function extract_data($string) {
global $request;
$found_matches = preg_match_all('/\[\"([a-z]+)\"\]/', $string, $matches);
if (!$found_matches) {
return null;
}
$current_data = $request;
foreach ($matches[1] as $name) {
if (key_exists($name, $current_data)) {
$current_data = $current_data[$name];
} else {
return null;
}
}
return $current_data;
}
$username = extract_data('request["user"]["username"]');
?>

Answer 2

function findInDepth($keys, $array){
$key = array_shift($keys);
if(!isset($array[$key])){
return FALSE;
}
if(is_array($array[$key])){
return findInDepth($keys, $array[$key]);
}
return $array[$key];
}
$key = "user[username]";
$keys = preg_split("/(\[|\])/", $key);
echo findInDepth($keys, $request);
This function solves my problem. It first splits the string (aka the input name) into an array of keys and then recessively searches in depth the array by keys until it finds a value which is not an array and returns FALSE otherwise.

Answer 3

You could separate keys with dots. Primitive example:
<?php
class ArrayDot
{
protected $array = [];
public function __construct(array $array) {$this->array = $array;}
public function get($path)
{
$array = $this->array;
foreach(explode('.', $path) as $key) {
$array = $array[$key];
}
return $array;
}
}
$array = [
'user' => [
'username' => 'tootski',
]
];
$a = new ArrayDot($array);
echo $a->get('user.username'); # tootski