How to sort an array of arrays in php?

Question

In php I have a numerical array of associative arrays:

mainArray: 
[
  array1:['title':'Record a','order':'2'],
  array2:['title':'Record b','order':'4'],
  array3:['title':'Record c','order':'1'],
  array4:['title':'Record d','order':'3']
]

What is the simplest way to sort mainArray by the 'order' value of each associative array?

Thanks

Answer 1

You can use usort function. Since PHP 5.4 you can use closure function:

usort($mainArray, function ($a, $b) {
  $a_val = (int) $a['order'];
  $b_val = (int) $b['order'];

  if($a_val > $b_val) return 1;
  if($a_val < $b_val) return -1;
  return 0;
});

Or version for PHP < 5.4:

usort($mainArray, 'myCompare');

function myCompare($a, $b) {
  $a_val = (int) $a['order'];
  $b_val = (int) $b['order'];

  if($a_val > $b_val) return 1;
  if($a_val < $b_val) return -1;
  return 0;
}