Assuming this array may or may not be redundantly nested and you're unsure of how deep it goes, this should flatten it for you:

function array_flatten($array) { 
  if (!is_array($array)) { 
    return FALSE; 
  } 
  $result = array(); 
  foreach ($array as value) { 
    if (is_array($value)) { 
      $result = array_merge($result, array_flatten($value)); 
    } 
    else { 
      $result[value; 
    } 
  } 
  return $result; 
} 

foreach($yourArray as $carArray)
{
 $result[]=$carArray["car"];
}

And your understanding of indexed arrays is wrong. That example output you've shown contains all those values, not indexes, and since you didn't specify an index it will start from 0 and so on.

The best way would be to manage your data structure as an object from the start if you have the ability:

$a = (object) array( ... ); $a->prop = $value; //and so on

But the quickest way would be the approach supplied by @CharlieS, using json_decode(json_encode($a)).

You could also run the array through a recursive function to accomplish the same. I have not benchmarked this against the json approach but:

function convert_array_to_obj_recursive($a) {
    if (is_array($a) ) {
        foreach(k => $v) {
            if (is_integer($k)) {
                // only need this if you want to keep the array indexes separate
                // from the object notation: eg. a['index'][$k] = convert_array_to_obj_recursive($v);
            }
            else {
                k] = convert_array_to_obj_recursive($v);
            }
        }

        return (object) $a;
    }

    // else maintain the type of $a
    return $a; 
}

Hope that helps.

EDIT: json_encode + json_decode will create an object as desired. But, if the array was numerical or mixed indexes (eg. array('a', 'b', 'foo'=>'bar') ), you will not be able to reference the numerical indexes with object notation (eg. o[1]). the above function places all the numerical indexes into the 'index' property, which is itself a numerical array. so, you would then be able to do $o->index[1]. This keeps the distinction of a converted array from a created object and leaves the option to merge objects that may have numerical properties.

Use array_map() or array_column()

// (PHP 4 >= 4.0.6, PHP 5, PHP 7)
print_r(array_map(function($a){return $a['sku'];}, $array));

// (PHP 5 >= 5.5.0, PHP 7)
print_r(array_column($array,'sku'));  

you new array will be

$new_array = array_map(function($a){return $a['sku'];}, $array);

$new_array = array_column($array,'sku');

This is a blanket statement on how to get your desired array :

$desired_array = array(array("0"=>"A"), array("0"=>"B"), array("0"=>"C"));

However, dynamically, you could do the following :

//Assume $original_array = array("0"=>"A", "1"=>"B", "2"=>"C");

$desired_array = array(); // New Array
for($i = 0; $i < count($original_array); $i++){ // Loop over all elements in original array
array_push($desired_array, array("0"=>$original_array[$i])); // Place each valueable as an array in new desired array
}

i don't know what you realy want to do .... maybe this could you help

<?php
   $new = array();
   foreach($oldArr as $arr) {
        $new[$arr['created']] = $arr;

   }
   print_r($new);
?>

You can use as follows :

$newArray = array();
foreach($arrayData as $key => $value) {
    foreach($value as $key2 => $value2) {
        $newArray[$key2] = $value2;
    }
}

Where $arrayData is your DB data array and $newArray will be the result.

It's not likely that the array you showed us is really what you're after.

PHP's arrays are so-called associative arrays, meaning that you can use anything to index them, not just numbers:

$myoptions = array(
  "1 day" => 24,
  "2 days" => 48,
  "3 days" => 72,
);

So,

echo $myoptions["3 days"]

or

$days = "3 days";
echo $myoptions[$days];

would directly return what you need. Of course, in real life applications, you would need to make sure that your input matches one of the indexes of the array.

Actually, but this is not something we can decide without knowing what you try to accomplish but in most cases you really need the opposite:

$myoptions = array(
  24 => "1 day",
  48 => "2 days",
  72 => "3 days",
);

That is, your program stores and uses the numeric part, the number of hours internally, and whenever you need to display the option it represents to the user, you do the conversion to the human readable format, not the other way around.