Foreach, special treatment of every n:th item (odd, even for example) [duplicate]

Answer 1

Add counter to it perhaps?

$counter = "";
foreach($array AS $variable){
  $counter +=1;
  // Here you will do your standard stuff you do always
  if($counter == 4){  // check for right counter value
    $counter = "";  // null the counter again
    // HERE you can do stuff that only happens every 4th iteration
  }
  // HERE you can carry on with your usual stuff that happens always
}

Of course there are many different ways to do this, this is in my eyes the simples one.