how to add elements to an array in a loop using php

Question

I am dynamically trying to populate a multidimensional array and having some trouble.

I have a list of US states. Associative array like this $states[nc], $states[sc

Answer 1

In PHP, you can fill an array without referring to the actual index.

$newArray = array();
foreach($var in $oldArray){
$newArray[] = $var;
}

Answer 2

foreach($states as $state) {
    $data[$state] = $state;

    foreach($state->cities as $city) {
      $data[$state][] = $city;
    }
}

Using empty brackets adds an element to the array.

Answer 3

To add an element, use empty brackets.

foreach($states as $state) {
    foreach($cities as $city) {
       $data[$state][] = $city;
    }
}

This will create an array like this

array(
  'nc' => array('city1', 'city2', ...),
  'sc' => array('city1', 'city2', ...)
)

See manual under "Creating/modifying with square bracket syntax"

Answer 4

The same way you add to an array when the key is not a concern:

$data[$state]['cities'][] = $city;