Question

I am trying to unset a group of array keys that have the same prefix. I can’t seem to get this to work.

foreach ($array as $key => $value) {
    unset($array['prefix_' . $key]);
    }

How can I get unset to see [‘prefix_’ . $key] as the actual variable? Thanks

UPDATE: The $array keys will have two keys with the same name. Just one will have the prefix and there are about 5 keys with prefixed keys:

Array {
   [name] => name
   [prefix_name] => other name
}

I don’t want to remove [name] just [prefix_name] from the array.

Answer 1

This works:

$array = array(
  'aa' => 'other value aa',
  'prefix_aa' => 'value aa',
  'bb' => 'other value bb',
  'prefix_bb' => 'value bb'
);

$prefix = 'prefix_';
foreach ($array as $key => $value) {
  if (substr($key, 0, strlen($prefix)) == $prefix) {
     unset($array[$key]);
  }
}

If you copy/paste this code at a site like http://writecodeonline.com/php/, you can see for yourself that it works.