note 113098 deleted from control-structures.foreach by tularis

Note Submitter: Anonymous ---- [quote] I want to add some inline comments to dtowell's piece of code about the iteration by reference: <?php $a = array('abe','ben','cam'); foreach ($a as $k=>&$n) $n = strtoupper($n); # At the end of this cycle the variable $n refers to the same memory as $a[2] # So when the second "foreach" assigns a value to $n : foreach ($a as $k=>$n) // notice NO reference here! echo "$n\n"; # it is also modifying $a[2] . # So on the three repetitions of the second "foreach" the array will look like: # 1. ('abe','ben','abe') - assigned the value of the first element to the last element # 2. ('abe','ben','ben') - assigned the value of the second element to the last element # 3. ('abe','ben','ben') - assigned the value of the third element to itself print_r($a); ?> [/quote] To resolve this problem - should always use unset after foreach: <?php $array = array('abe','ben','cam'); foreach ( $array as $key=>&$val ) {} unset($key); unset($val); foreach ( $array as $key=>$val ) {} unset($key); unset($val); print_r($array);