php - Array unserialize issue returning null/false -

i've got array being returned in format:

a:1:{i:0;i:305;}

i can't seem unserialize() access 305. have idea on can do?

query in wordpress:

$order_id = $wpdb->get_row("select meta_value wp_postmeta post_id=" . $t->object_id . " , meta_key='wpc_inv_order_id");

i attempted use:

$str = $order_id->meta_value; $a = unserialize($str); var_dump($a); echo $a;

which resulted in bool(false).

however, appears doing echo $order_id->meta_value; somehow unserialized , giving me id value in serialized array.

so doing:

$str = $order_id->meta_value; echo $str;

i'm getting output 305 on above.

thank help!

looking result of unserialize

$str = 'a:1:{i:0;i:305;}'; var_dump($a = unserialize($str));  array(1) {   [0]=>   int(305) }

so take by$a[0];

Call