php - Get array's key recursively and create underscore separated string

Question

Right now i got an array which has some sort of information and i need to create a table from it. e.g.

Student{
      [Address]{
              [StreetAddress] =>"Some Street"
              [StreetName] => "Some Name"
      }
      [Marks1] => 100
      [Marks2] => 50
    }

Now I want to create database table like which contain the fields name as :

Student_Address_StreetAddress
Student_Address_StreetName
Student_Marks1
Student_Marks2

It should be recursive so from any depth of array it can create the string in my format.

Answer 1

You can use the RecursiveArrayIterator and the RecursiveIteratorIterator (to iterate over the array recursively) from the Standard PHP Library (SPL) to make this job relatively painless.

$iterator = new RecursiveIteratorIterator(new RecursiveArrayIterator($arr));
$keys = array();
foreach ($iterator as $key => $value) {
    // Build long key name based on parent keys
    for ($i = $iterator->getDepth() - 1; $i >= 0; $i--) {
        $key = $iterator->getSubIterator($i)->key() . '_' . $key;
    }
    $keys[] = $key;
}
var_export($keys);

The above example outputs something like:

array (
  0 => 'Student_Address_StreetAddress',
  1 => 'Student_Address_StreetName',
  2 => 'Student_Marks1',
  3 => 'Student_Marks2',
)