居然还有这种操作 -- 学到老活到老系列

break#

<?php
$arr = array('one', 'two', 'three', 'four', 'stop', 'five');
while (list(, $val) = each($arr)) {
if ($val == 'stop') {
break; /* You could also write 'break 1;' here. */
}
echo "$val
\n";
}

/* Using the optional argument. */

$i = 0;
while (++$i) {
switch ($i) {
case 5:
echo "At 5
\n";
break 1; /* Exit only the switch. /
case 10:
echo "At 10; quitting
\n";
break 2; / Exit the switch and the while. */
default:
break;
}
}
?>
whaaaaaaaat？还有这种操作？再来看看手册

看来是自己out了。

Version	Description
5.4.0	break 0; is no longer valid. In previous versions it was interpreted the same as break 1;
5.4.0	Removed the ability to pass in variables (e.g., $num = 2; break $num;) as the numerical argument.