Reputation: 593
for example:
$numbers = array(1, 2, 3, 4, 5);
foreach($numbers as $value)
{
echo $value;
}
what does as
do, I assume it's a keyword because it is highlighted as one in my text editor. I checked the keyword list at http://www.php.net/manual/en/reserved.keywords.php and the as
keyword was present. It linked to the foreach
construct page, and from what I could tell didn't describe what the as
keyword did. Does this as
keyword have other uses or is it just used in the foreach
construct?
Upvotes: 1
Views: 100
Reputation: 780724
as
is just part of the foreach
syntax, it's used to specify the variables that are assigned during the iteration. I don't think it's used in any other context in PHP.
Upvotes: 1
Reputation: 16656
It's used to iterate over Iterators, e.g. arrays. It reads:
foreach value in $numbers, assign the value to $value.
You can also do:
foreach ($numbers as $index => $value) {
}
Which reads:
foreach value in $numbers, assign the index/key to $index and the value to $value.
To demonstrate the full syntax, lets say we have the following:
$array = array(
0 => 'hello',
1 => 'world')
);
For the first iteration of our foreach loop, $index
would be 0
and $value
would be 'hello'. For the second iteration of our foreach loop, $index
would be 1
, and $value
would be 'world'.
Foreach loops are very common. You may have seen them as for..in loops in other languages.
For the as
keyword, you're saying:
for each value in $numbers AS $value
It's a bit awkward, I know. As far as I know, the as
keyword is only used with foreach loops.
Upvotes: 2