两组二维数组，如何快速找出差集元素

Question

$arr1 = [
    ['number' => '1001', 'empno' => '9991','title'=>'财务'],
    ['number' => '1001', 'empno' => '9992','title'=>'财务'],
    ['number' => '1002', 'empno' => '9991','title'=>'财务'],
    ['number' => '1002', 'empno' => '9992','title'=>'财务'],
    ['number' => '1001', 'empno' => '9990','title'=>'财务']
];
$arr2 = [
    ['number' => '1001', 'empno' => '9991','title'=>'财务'],
    ['number' => '1001', 'empno' => '9992','title'=>'财务'],
    ['number' => '1002', 'empno' => '9991','title'=>'财务'],
    ['number' => '1002', 'empno' => '9992','title'=>'财务']
];

如有以上两组数组，就如唯一键值一样，number与empno不能出现同一组为重复的数组，以上$arr1,最后一位元素为差集元素(['number' => '1001', 'empno' => '9990','title'=>'财务'])，就是不相同的元素。请问怎么用除了套用两个foreach外快速的查找出来呢

Answer 1

$arr3 = array_filter($arr1, function ($v) use ($arr2) { return !in_array($v, $arr2); }); 最简单的写法不过这个写法有个缺陷只能找到$arr1中不包含$arr2的项，要找出2个数组差集得再封装一下