PHP: Limit foreach() statement? [closed]
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Closed 9 years ago.
Improve this questionHow can i limit a foreach() statement? Say i only want it to run the first 2 'eaches' or something?
There are many ways, one is to use a counter:
$i = 0;
foreach ($arr as $k => $v) {
/* Do stuff */
if (++$i == 2) break;
}
Other way would be to slice the first 2 elements, this isn't as efficient though:
foreach (array_slice($arr, 0, 2) as $k => $v) {
/* Do stuff */
}
You could also do something like this (basically the same as the first foreach, but with for):
for ($i = 0, reset($arr); list($k,$v) = each($arr) && $i < 2; $i++) {
}
You can either use
break;
or
foreach() if ($tmp++ < 2) {
}
(the second solution is even worse)
you should use the break statement
usually it's use this way
$i = 0;
foreach($data as $key => $row){
if(++$i > 2) break;
}
on the same fashion the continue statement exists if you need to skip some items.
In PHP 5.5+, you can do
function limit($iterable, $limit) {
foreach ($iterable as $key => $value) {
if (!$limit--) break;
yield $key => $value;
}
}
foreach (limit($arr, 10) as $key => $value) {
// do stuff
}
Generators rock.
this is best solution for me :)
$i=0;
foreach() if ($i < yourlimitnumber) {
$i +=1;
}
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