I have a loop that is doing some error checking in my PHP code. Originally it looked something like this...
foreach($results as $result) {
if (!$condition) {
$halt = true;
ErrorHandler::addErrorToStack('Unexpected result.');
}
doSomething();
}
if (!$halt) {
// do what I want cos I know there was no error
}
This works all well and good, but it is still looping through despite after one error it needn't. Is there a way to escape the loop?
You are looking for the break statement.
$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<br />\n";
}
As stated in other posts, you can use the break keyword. One thing that was hinted at but not explained is that the keyword can take a numeric value to tell PHP how many levels to break from.
For example, if you have three foreach loops nested in each other trying to find a piece of information, you could do 'break 3' to get out of all three nested loops. This will work for the 'for', 'foreach', 'while', 'do-while', or 'switch' structures.
$person = "Rasmus Lerdorf";
$found = false;
foreach($organization as $oKey=>$department)
{
foreach($department as $dKey=>$group)
{
foreach($group as $gKey=>$employee)
{
if ($employee['fullname'] == $person)
{
$found = true;
break 3;
}
} // group
} // department
} // organization
break; leaves your loop.
continue; skips any code for the remainder of that loop and goes on to the next loop, so long as the condition is still true.
All of these are good answers, but I would like to suggest one more that I feel is a better code standard. You may choose to use a flag in the loop condition that indicates whether or not to continue looping and avoid using break all together.
$arr = array('one', 'two', 'three', 'four', 'stop', 'five');
$length = count($arr);
$found = false;
for ($i = 0; $i < $length && !$found; $i++) {
$val = $arr[$i];
if ($val == 'stop') {
$found = true; // this will cause the code to
// stop looping the next time
// the condition is checked
}
echo "$val<br />\n";
}
I consider this to be better code practice because it does not rely on the scope that break is used. Rather, you define a variable that indicates whether or not to break a specific loop. This is useful when you have many loops that may or may not be nested or sequential.
$arr = array('one', 'two', 'three', 'four', 'stop', 'five');
foreach ($arr as $val) {
if ($val == 'stop') {
break; /* You could also write 'break 1;' here. */
}
echo "$val<br />\n";
}
