从另一个数组中的键获取多维数组值

Question

I've got an array containing values I wish to use as keys, such as:

$keys = array("first", "second", "third", "fourth");

The count and contents of these values will be changing dynamically within a loop. I want them to become the keys of a multidimensional array, but the count of the keys array will always be changing, so while this would work for that first array of keys:

$multidimensional[$keys[0]][$keys[1]][$keys[2]][$keys[3]] = "some value";

Later in the loop the keys may be something like:

$keys = array("first", "second", "gamma", "delta", "theta", "kappa");

So using this in the loop:

$multidimensional[$keys[0]][$keys[1]][$keys[2]][$keys[3]] = "some value";

Will not work, and needs to be dynamic too based on the count of the keys.

I've gone through each of the array functions in the PHP manual and can't seem to find something that fulfills this purpose. Am I totally overlooking something basic here? Maybe some curly brace magic?

Answer 1

There you go...

function setMultidimensionalValue($value, array $keys, array $multidimensional)
{
  $node = &$multidimensional;
  foreach ($keys as $key)
  {
    if (!isset($node[$key]))
      $node[$key] = null;
    $node = &$node[$key];
  }
  $node = $value;
  return $multidimensional;
}

// Example of usage
$multidimensional = array();
var_dump(setMultidimensionalValue('value', array('first', 'second', 'third'), $multidimensional));