Question

I was looking through some inherited PHP code when I found the following:

$emails=array();
foreach($usrs as $usr){
    $emails[]=$usr['email'];
}

It’s clear that this is trying to extract the ’email’ property of each object in a list of users and hold them in an array. That’s what I want it to do. Does this do that? I’ve never seen such a thing work this way. I replaced it with

array_push($emails, $usr['email']);

since I know that that does what I intend it to.

Answer 1

The two are the same, almost.

It will add an item to the end of the array, just as array_push does. The only difference is array_push returns the new number of elements in the array. The empty bracket notation does not return anything, obviously.

You should get comfortable with this notation, it’s easier to type and read.

array_push on PHP docs mentions the use of this notation and covers two other differences as well.

Note: If you use array_push() to add one element to the array it’s better to use $array[] = because in that way there is no overhead of calling a function.

Note: array_push() will raise a warning if the first argument is not an array. This differs from the $var[] behaviour where a new array is created.