Question

我的基本数组结构如下

$user_data = [
            [
                'user_id'           => '1',
                'user_name'         => 'numpty',
                'email'             => 'john@somewhere.com',
                'first_name'        => 'John',
                'last_name'         => 'Smith'
            ],
            [
                'user_id'           => '2',
                'user_name'         => 'fairy52',
                'email'             => 'natasha@legs.com',
                'first_name'        => 'Natasha',
                'last_name'         => 'Jones'
            ],
            [
                'user_id'           => '3',
                'user_name'         => 'angie_turmoil',
                'email'             => 'ange@nightmare.com',
                'first_name'        => 'Angela',
                'last_name'         => 'Swift'
            ],
            [
                'user_id'           => '4',
                'user_name'         => 'dastardly_dan',
                'email'             => 'daniel@aol.com',
                'first_name'        => 'Daniel',
                'last_name'         => 'McNash'
            ],
            [
                'user_id'           => '5',
                'user_name'         => 'horse',
                'email'             => 'fred@features.com',
                'first_name'        => 'Frederick',
                'last_name'         => 'Walsh'
            ]
        ];

$user_followers = [
                    [
                        'user_id'   => '1',
                        'followers' => ['3', '4', '5']
                    ],
                    [
                        'user_id'   => '2',
                        'followers' => ['1', '5']
                    ],
                    [
                        'user_id'   => '3',
                        'followers' => ['1', '5', '4']
                    ],
                    [
                        'user_id'   => '4',
                        'followers' => ['3', '1', '5']
                    ],
                    [
                        'user_id'   => '5',
                        'followers' => ['1', '2', '4']
                    ],
                ];

我需要做的是为每个$user_data根据user_id返回关注者名称，因此$user_data中的第一条记录需要返回姓名

angie_turmoil
dastardly_dan
horse

据我所知，这不是传统的数据存储方式，但它是学习OOP PHP的原型项目，我不需要使用数据库进行数据存储。

Answer 1

正如您当前构建的数据一样，如果您想尝试简单的foreach，您可以执行类似的操作。考虑这个例子：

$data = array();
foreach($user_followers as $index => $element) {
    $current_user = $element['user_id']; // get the current user in iteration
    $followers = $element['followers']; // get his/her followers
    foreach($followers as $f_user_id) {
        foreach($user_data as $key => $value) { // search the current user followers inside the user_data
            if($value['user_id'] == $f_user_id) {
                $data[$current_user]['follower_names'][] = $value['user_name'];
            }
        }
    }

}

print_r($data);

示例输出：

Array
(
    [1] => Array
    (
        [follower_names] => Array
        (
            [0] => angie_turmoil
            [1] => dastardly_dan
            [2] => horse
        )

    )

    [2] => Array
    (
        [follower_names] => Array
        (
            [0] => numpty
            [1] => horse
        )

    )

    [3] => Array
    (
        [follower_names] => Array
        (
            [0] => numpty
            [1] => horse
            [2] => dastardly_dan
        )

    )

// and so on.

注意：他们的数组键是user_id，里面的值是他们的追随者。

Answer 2

这有点疯狂，但嘿，它有效：

$list = array();    
foreach ($user_data as $user) 
    foreach ($user_followers as $followers) 
        if ($followers['user_id']==$user['user_id'])
            foreach ($followers['followers'] as $f_id)
                foreach ($user_data as $user2)
                    if ($user2['user_id']==$f_id)
                        $list[$user['user_name']][] = $user2['user_name'];

print_r($list);

输出：

Array
(
    [numpty] => Array
        (
            [0] => angie_turmoil
            [1] => dastardly_dan
            [2] => horse
        )

    [fairy52] => Array
        (
            [0] => numpty
            [1] => horse
        )

    [angie_turmoil] => Array
        (
            [0] => numpty
            [1] => horse
            [2] => dastardly_dan
        )

    [dastardly_dan] => Array
        (
            [0] => angie_turmoil
            [1] => numpty
            [2] => horse
        )

    [horse] => Array
        (
            [0] => numpty
            [1] => fairy52
            [2] => dastardly_dan
        )
)

基于来自不同阵列php的数据从一个阵列获取数据

2 个答案: