array_push

The $array[] = $var statement differs from array_push($array, $var) in that
it can operate on uninitialized variables as well. array_push only works
with initialized arrays.

la solution $array[$key]=$value; est une bonne solution pour ajouter une
paire à un tableau, mais elle pose problème lorsqu'on a des $key
identiques. Array_push est donc ici une bonne alternative.

Array_push also works fine with multidimensional arrays. Just make sure the
element is defined as an array first.

$array["element"][$element]["element"] = array();
array_push ($array["element"][$element]["element"],
"banana");

Interesting! Maybe $a[]=$b is NOT the same as array_push($a, $b) - when you
want the VALUE of an array to also be an array.

$a = array();
$b = array("one","example","array");
$c = array("another","silly","test");

$a[] = $b;  /* ERROR */
$a[] = $c;  /* ERROR */

but...

array_push($a, $b);  /* WORKS */
array_push($a, $c);  /* WORKS */

array_push() doesn't seem to allow you to push a key=>value pair onto
the array.

i.e.:
$myarray = array ();
          :
array_push($myarray,"mykey"=>"myvalue");

produces a parsing error.

Regarding:
Carl wrote that: "array_push() doesn't seem to allow you to push a
key=>value pair onto the array."

The correct syntax for this would be:
$array['newkey']=$newvalue;

You should not need the array_push function, but if so the example should
read:
array_push($myarray,array("mykey"=>"myvalue"));

This will not return a syntax error.

I noticed that when building a large array, array_push($array, $value)
didn't seem to be quite as fast as $array[] = $value. Using the latter
would therefore be a useul optimisation if you can guarantee unique keys
(e.g. reading from a DB table with an id field).

Static.

Anonymous said:

array_push($myarray,array("mykey"=>"myvalue"));
This will not return a syntax error.

But this is totally incorrect. It's equivalent to:

$myarray[count($myarray)] =
array("mykey"=>"myvalue"));

---------------------------------------
Anonymous said:

array_push($myarray,array("mykey"=>"myvalue"));
This will not return a syntax error.

But this is totally incorrect. It's equivalent to:

$myarray[count($myarray)] =
array("mykey"=>"myvalue"));
---------------------------------------
yes, but as you can see in the function definition, 
array_push($arr, $newval) 
is the same as 
$arr[] = $newval
and therefor 
array_push($arr, array("key" => "val") 
is the same as $arr[] = array("key" => "val")

here's a function which will perform as you want to:
---------------------------------------
function array_push_assoc(&$array, $key, $val)
{
    if (!is_array($array)) {
        return 0;
    }
    
    $args = func_get_args();
    
    for($i = 1; $i < func_num_args(); $i + 2) {
        if (is_string($args[$i]) && trim($args[$i]) !=
"") {
            $array[$args[$i]] = $args[$i + 1];
        }
    }
    return sizeof($array);
}
---------------------------------------

Here`s a shorter way of adding "key=>value" values

$myarray = array( "mykey"=>"myvalue" );
$myarray = array_merge( $myarray,array( "mykey2" =>
"myvalue2" ));

But that doesn't work for integer keys, because they will be renumbered by
the array_merge(). (Which is the problem that brought me to this exact page
;))

If you want to use integer keys simply treat it as an 'ordinary' array.

$user_arr = array();

$user_id = 4;
$user_name = 'John';
$user_arr[$user_id] = $user_name;

$user_id = 346;
$user_name = 'Steve';
$user_arr[$user_id] = $user_name;

$user_id = 652;
$user_name = 'Maria';
$user_arr[$user_id] = $user_name;

All slots in between the three user IDs will not be allocated and
sizeof($user_arr) will return 3 and not 653.