从另一个多维数组PHP创建多维数组

Question

可以说我有一个像这样的多维数组：

$results = array(
    0 => array(
        'fruit' => 'apple',
        'colour' => 'green',
        'amount' => 50
    ),
    1 => array(
        'fruit' => 'orange',
        'colour' => 'orange',
        'amount' => 25
    ),
    2 => array(
        'fruit' => 'banana',
        'colour' => 'yellow',
        'amount' => 7
    )
);

我只想使用特定对象创建一个新的多维数组：

$newarray = array(
    0 => array(
        'fruit' => 'apple',
        'amount' => 50
    ),
    1 => array(
        'fruit' => 'orange',
        'amount' => 25
    ),
    2 => array(
        'fruit' => 'banana',
        'amount' => 7
    )
);

我该怎么做？ 我读过一些不同的东西，似乎array_map或array_column可能是答案，但我还没有找到适合我情况的示例。

我到目前为止：

$newarray = array();
foreach ($results as $result) {
    if (!empty($result['fruit'])) {
      // create new array here but how do I specify the key => values?
    }
}

Answer 1

如果键是固定的，并且您没有太多键，则这是合适的：

$results = array(
    0 => array(
        'fruit' => 'apple',
        'colour' => 'green',
        'amount' => 50
    ),
    1 => array(
        'fruit' => 'orange',
        'colour' => 'orange',
        'amount' => 25
    ),
    2 => array(
        'fruit' => 'banana',
        'colour' => 'yellow',
        'amount' => 7
    )
);

$new = array();
foreach($results as $value){
    $new[] = array(
        'fruit' => $value['fruit'],
        'amount' => $value['amount']
    );
}
var_dump($new);

得到：

array (size=3)
  0 => 
    array (size=2)
      'fruit' => string 'apple' (length=5)
      'amount' => int 50
  1 => 
    array (size=2)
      'fruit' => string 'orange' (length=6)
      'amount' => int 25
  2 => 
    array (size=2)
      'fruit' => string 'banana' (length=6)
      'amount' => int 7

Answer 2

无论如何，这是您不正确的？

foreach ($results as $key) {
    unset ($results[$key]['colour']);
}

print_r($results);

输出：

Array
(
[0] => Array
    (
        [fruit] => apple
        [amount] => 50
    )

[1] => Array
    (
        [fruit] => orange
        [amount] => 25
    )

[2] => Array
    (
        [fruit] => banana
        [amount] => 7
    )

)

Answer 3

将密钥设置在“ $ keys_to_search”上。 胜过使用unset。

$keys_to_search = ['fruit' => '','colour' => ''];

$results = array(
    0 => array(
        'fruit' => 'apple',
        'colour' => 'green',
        'amount' => 50
    ),
    1 => array(
        'fruit' => 'orange',
        'colour' => 'orange',
        'amount' => 25
    ),
    2 => array(
        'fruit' => 'banana',
        'colour' => 'yellow',
        'amount' => 7
    )
);




foreach($results as $key => $value){
    $result[] = array_intersect_key($value, $keys_to_search);  
}

print_r($result);