# diffKeys方法 與另外一個集合或 PHP 數組的「鍵」進行比較，然后返回原集合中存在而給定的集合中不存在「鍵」所對應的鍵值對。 ``` $collection = collect([ 'one' => 10, 'two' => 20, 'three' => 30, 'four' => 40, 'five' => 50, ]); $diff = $collection->diffKeys([ 'two' => 2, 'four' => 4, 'six' => 6, 'eight' => 8, ]); $diff->all(); // ['one' => 10, 'three' => 30, 'five' => 50] ```