continue
(PHP 4, PHP 5, PHP 7)
continue is used within looping structures to skip the rest of the current loop iteration and continue execution at the condition evaluation and then the beginning of the next iteration.
Note: In PHP the switch statement is considered a looping structure for the purposes of continue. continue behaves like break (when no arguments are passed). If a switch is inside a loop, continue 2 will continue with the next iteration of the outer loop.
continue accepts an optional numeric argument which tells it how many levels of enclosing loops it should skip to the end of. The default value is 1, thus skipping to the end of the current loop.
<?php
while (list($key, $value) = each($arr)) {
if (!($key % 2)) { // skip even members
continue;
}
do_something_odd($value);
}
$i = 0;
while ($i++ < 5) {
echo "Outer<br />\n";
while (1) {
echo "Middle<br />\n";
while (1) {
echo "Inner<br />\n";
continue 3;
}
echo "This never gets output.<br />\n";
}
echo "Neither does this.<br />\n";
}
?>Omitting the semicolon after continue can lead to confusion. Here's an example of what you shouldn't do.
<?php
for ($i = 0; $i < 5; ++$i) {
if ($i == 2)
continue
print "$i\n";
}
?>One can expect the result to be:
0
1
3
4but, in PHP versions below 5.4.0, this script will output:
2because the entire continue print "$i\n"; is evaluated as a single expression, and so print is called only when $i == 2 is true. (The return value of print is passed to continue as the numeric argument.)
Note: As of PHP 5.4.0, the above example will raise an
E_COMPILE_ERRORerror.
Version | Description |
|---|---|
5.4.0 | continue 0; is no longer valid. In previous versions it was interpreted the same as continue 1;. |
5.4.0 | Removed the ability to pass in variables (e.g., $num = 2; continue $num;) as the numerical argument. |
← break
switch →
© 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
本文档系腾讯云开发者社区成员共同维护，如有问题请联系 cloudcommunity@tencent.com
