PHP Array_merge involving $_SESSION doesn't work

Question

This code doesn't seem to work:

session_start();
$_SESSION['filtros_web_jobs'] = array();
array_merge( $_SESSION['filtros_web_jobs'], $_POST['filtros_web_form'] );
var_dump($_SESSION);
var_dump($_POST);
session_write_close();
exit;

Outputs:

array(1) {
  ["filtros_web_jobs"]=>
  array(0) {
  }
}
array(1) {
  ["filtros_web_form"]=>
  array(1) {
    ["cola"]=>
    string(18) "fisica_Renova_zxcv"
  }
}

Any clue?

Thanks

Answer 1

Array_merge returns an array. It does not mutate the arrays that are passed to it.

$merged = array_merge( $_SESSION['filtros_web_jobs'], $_POST['filtros_web_form'] );

Answer 2

From Array merge on PHP.net

Return Values

Returns the resulting array.

You aren't setting the output to anything - Try this:

$output = array_merge( $_SESSION['filtros_web_jobs'], $_POST['filtros_web_form'] );
print_r($output);

Answer 3

array_merge returns the new, merged array. Try:

$a = array_merge( $_SESSION['filtros_web_jobs'], $_POST['filtros_web_form'] );
var_dump($a);

Answer 4

You have not cached the data that array_merge function is giving you after merging the arrays.

 $mergedArray = array_merge( $_SESSION['filtros_web_jobs'], $_POST['filtros_web_form'] );