php将两个不同长度数组相同的key合并到一个数组，不同的key也合并进去

1.处理前的数组：

 1,
    'user_name'=>'test1'
    ),
    array(
    'id' => 2,
    'user_name'=>'test2'
    ),
    array(
    'id' => 3,
    'user_name'=>'test3'
    )
);
$arr2 = array(
     array(
    'id' => 1,
    'shop_name'=>'shop1'
    ),
    array(
    'id' => 5,
    'shop_name'=>'shop2'
    ),
    array(
    'id' => 3,
    'shop_name'=>'shop3'
    ),
    array(
    'id' => 4,
    'shop_name'=>'shop4'
    )
);

2.根据2个数组id相同的一维数组，将$arr2的shop_name添加到$arr1，将$arr1的user_name添加到$arr2,如果没有相同的id，shop_name和user_name为空，处理后的数组：

$new_arr =array(
    array(
    'id' => 1,
    'user_name'=>'test1',
    'shop_name'=>'shop1'
    ),
    array(
    'id' => 2,
    'user_name'=>'test2',
    'shop_name'=>''
    ),
    array(
    'id' => 3,
    'user_name'=>'test3',
    'shop_name'=>'shop3'
    ),
    array(
    'id' => 4,
    'user_name'=>'',
    'shop_name'=>'shop4'
    ),
    array(
    'id' => 5,
    'user_name'=>'',
    'shop_name'=>'shop2'
    ),
);

3：处理的过程

$new_arr = array();
foreach ($arr1 as $val) {
    $new_arr[$val['id']] = array('id'=>$val['id'],'shop_name'=>'','user_name'=>$val['user_name']);
}
foreach ($arr2 as $val) {
    if(isset($new_arr[$val['id']])){
        $new_arr[$val['id']]['shop_name'] = $val['shop_name'];
    }else{
        $new_arr[$val['id']] = array('id'=>$val['id'],'shop_name'=>$val['shop_name'],'user_name'=>'',);
    }
}
var_dump(array_values($new_arr));