取同層級頁面id
/**
取同層級頁面id
bool $with_parent = true ; 包含父層id
return array
https://v123.tw
*/
function v123tw_get_same_level_post_id_of_current_post($with_parent=false){
if(!$id = get_the_ID())return array();
if($pid = wp_get_post_parent_id( $id ))$id = $pid;
if(!$id)return array();[......]