我如何编写这个foreach循环作为任何其他类型的循环？

Question

foreach ($a as $b)
{
do function
}

Answer 1

while ($b.MoveNext())
{
    $a = $b.Current;
}

Answer 2

reset($a);
while (list($key, $value) = each($a)) { 
  //...
}

$keys = array_keys($a);
while (($key = array_shift($keys)) !== NULL))
{
  $b = $a[$key];
}