Question

What’s the best way in PHP to sort an array of arrays based on array length?

e.g.

$parent[0] = array(0, 0, 0); $parent[2] = array('foo', 'bar', 'b', 'a', 'z'); $parent[1] = array(4, 2);  $sorted = sort_by_length($parent)  $sorted[0] = array(4, 2); $sorted[1] = array(0, 0, 0); $sorted[2] = array('foo', 'bar', 'b', 'a', 'z'); 

Answer 1

This will work:

function sort_by_length($arrays) {     $lengths = array_map('count', $arrays);     asort($lengths);     $return = array();     foreach(array_keys($lengths) as $k)         $return[$k] = $arrays[$k];     return $return; } 

Note that this function will preserve the numerical keys. If you want to reset the keys, wrap it in a call to array_values().