What's better to use in PHP, $array[] = $value or array_push($array, $value)?

Question

What\'s better to use in PHP for appending an array member,

$array[] = $value;

or

array_push($array, $value);

Answer 1

Although the question was more about performance, people will come to this question wondering if it's good practise to use array_push or $arr[].

The function might mean lesser lines for multiple values:

// 1 line:
array_push($arr, "Bob", "Steve");
// versus 2 lines:
$arr[] = "Bob";
$arr[] = "Steve";

However, array_push...

• cannot receive the array keys
• breaks the needle/haystack naming convention
• is slower, as has been discussed

I'll be sticking with $arr[].

Answer 2

No benchmarks, but I personally feel like $array[] is cleaner to look at, and honestly splitting hairs over milliseconds is pretty irrelevant unless you plan on appending hundreds of thousands of strings to your array.

Edit: Ran this code:

$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    $array[] = $i;
}
print microtime(true) - $t;
print '<br>';
$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    array_push($array, $i);
}
print microtime(true) - $t;

The first method using $array[] is almost 50% faster than the second one.

Some benchmark results:

Run 1
0.0054171085357666 // array_push
0.0028800964355469 // array[]

Run 2
0.0054559707641602 // array_push
0.002892017364502 // array[]

Run 3
0.0055501461029053 // array_push
0.0028610229492188 // array[]

This shouldn't be surprising, as the PHP manual notes this:

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.

The way it is phrased I wouldn't be surprised if array_push is more efficient when adding multiple values. EDIT: Out of curiosity, did some further testing, and even for a large amount of additions, individual $array[] calls are faster than one big array_push. Interesting.

Answer 3

Second one is a function call so generally it should be slower than using core array-access features. But I think even one database query within your script will outweight 1.000.000 calls to array_push().

Answer 4

From the php docs for array_push:

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.