Use variable with part of array path to output array value - php

Question

I have an array like so:
$cars = array(
'type' => array(
'brand' => array(
'car' => 'Honda',
),
),
);
And I also have a string like so:
$path = "type][brand][car";
I'd like to return a value of car from $cars array using $path string, but of course this won't work:
echo $cars[$path];
The output I'd like to have is: "Honda". How this should be done?

Answer 1

Here is basicly what I understood you want to achieve in a simple function, that uses the parents array to get a nested value:
<?php
$cars = array(
'type' => array(
'brand' => array(
'car' => 'Honda',
),
),
);
$parents = array('type', 'brand', 'car');
// you could also do:
// $path = "type][brand][car";
// $parents = explode("][", $path);
function GetCar($cars, $parents) {
foreach($parents as $key) {
$cars = $cars[$key];
// echo $key."<br>";
}
return $cars;
}
var_dump(GetCar($cars, $parents)); // OUTPUT: string(5) "Honda"
echo GetCar($cars, $parents); // OUTPUT: Honda
A snippet: https://3v4l.org/OKrQN
I still think, that there is a better solution for what you need in a bigger picture (that I don't know)

Answer 2

Here is the correct answer, I am not just saying that as I've done this many times before. And I have really analyzed the problem etc...
$array = array(
'type' => array(
'brand' => array(
'car' => 'Honda',
),
),
);
$path = "type][brand][car";
function transverseGet($path, array $array, $default=null){
$path = preg_split('/\]\[/', $path, -1, PREG_SPLIT_NO_EMPTY);
foreach($path as $key){
if(isset($array[$key])){
$array = $array[$key];
}else{
return $default;
}
}
return $array;
}
print_r(transverseGet($path, $array));
Output
Honda
Sandbox
The trick is, every time you find a key from the path in the array you reduce the array to that element.
if(isset($array[$key])){
$array = $array[$key];
At the end you just return whatever is left, because your out of path parts to run so you can assume its the one you want.
If it doesn't find that key then it returns $default, you can throw an error there if you want.
It's actually pretty simple to do, I have this same setup for set,get,isset - key transversal
Like a Ninja ()>==<{>============>

Answer 3

If you require to use that specific structure you could do something like this:
$path = "type][brand][car";
$path_elements = explode("][", $path);
This way you get an array with each of the components required, and you'll have to do something like:
echo $cars[$path_elements[0]][$path_elements[1]][$path_elements[2]];
Of course that is a little bit too static and needs the same 3 level element structure.

Answer 4

May be this can resolve the problem :
strong text$cars = array( 'type' => array(
'brand' => array(
'car' => 'Honda',
), ), );
$path = "type][brand][car";
preg_match_all('/[a-z]+/', $path,$res);
$re = $res[0];
echo $cars[$res[0][$res[1]][$res[2]];