配列の連結して1つの配列

array_merge
<?php
$array1 = array ("key1" => "val1", 2, 4);
$array2 = array ("a", "b", "key1" => "val2", "etc" => "val3", 4);
$result = array_merge ($array1, $array2);
print_r($result);
?> 

同じkeyは後ろが優先。

[key1] => val2
[0] => 2
[1] => 4
[2] => a
[3] => b
[etc] => val3
[4] => 4