PHP Source:
<
!DOCTYPE
html
>
<
html
>
<
body
>
<?php
$a=
array
(
"Volvo"
=>
"XC90"
,
"BMW"
=>
"X5"
,
"Toyota"
=>
"Highlander"
);
print_r(array_keys($a));
?>
<
/body
>
<
/html
>
Result: