Dropwizard View包含几个Freemarker模板(Dropwizard View includes several Freemarker templates)

 如果你必须多次这样做，我建议你从$ p类中的方法返回属性数组并使用 
 
array_diff($attributes, $p->getAttributes());

This is what I finally did:
 
$all_attributes = array("a", "b", "c", "d","e","f", "g","h" ,"i","j","k","l");
$attributes = array();
foreach($allpkg as $p) {
  foreach($all_attributes as $key=> $a) {
    if ($p->getAttribute($a) && (!in_array($a, $attributes))) {
      array_push($attributes,$a);
    }                           
  }
}
 
EDIT: Solution has been edited due to my EDIT in the question itself...(aaawww, sorry for confusion). Maybe not the most elegant and certainly not the most efficient (copying all needed elements...). But I have clear control about what's going on and it works :)