Question

如何通过将键替换为值来仅使用foreach循环来修改以下代码？例如，沙拉，鸡肉和煎饼键就是价值。

$meals = array(
    'Lunch' => array(
            'salad' => 'italian',
            'salad2' => 'ranch',
            'salad3' => 'sesame',
            'salad4' => 'bluecheese'
        ), 

    'Dinner' => array(
            'chicken' => 'grilled',
            'chicken2' => 'baked',
            'chicken3' => 'steamed',
            'chicken4' => 'fried',
            'chicken5' => 'broiled'
        ), 

    'Breakfast' => array(
        'pancakes' => 'blueberry',
        'pancakes2' => 'cherry',
        'pancakes3' => 'strawberry',
        'pancakes4' => 'lemon'
        )
);

$newkey = array();

foreach($meals as $key => $value) {
    unset($value);
    // foreach ($)...
}


print_r($meals);

Answer 1

修改

如果你不能使用array_flip（），那么你需要做两个循环：每餐一个，每餐一个。

示例：

foreach ($meals as $meal => $mealOptions) { $revisedMealOptions = array(); foreach ($mealOptions as $originalKey => $newKey) { $revisedMealOptions[$newKey] = $originalKey; } $meals[$meal] = $revisedMealOptions; }

原始答案

你所追求的并不完全清楚。如果你想要的只是转向：

'Lunch' => array( 'salad' => 'italian' );

到

'Lunch' => array( 'italian' => 'salad' );

使用 array_flip（）。

示例：

$meals['Lunch'] = array_flip($meals['Lunch']);

请参阅http://php.net/manual/en/function.array-flip.php。

Answer 2

抱歉，我是初学者。我需要使用嵌套的$ foreach循环来解决这个问题。对于I类，不允许使用array_flip函数。我试过了

$newkey = array();

foreach($meals as $key => $value) {
  $newkey[] = $value; 
     foreach ($value as ){
    }
  }

Answer 3

所以，它会读到：

基本上我需要它阅读：

阵列（

[Lunch] => array(
        [italian] => salad,
        [ranch] => salad2,
        [sesame] => salad3,
        [bluecheese] => salad4
    )
 )

Answer 4

最简单的方法就是这样：

$meals = array(
    'Lunch' => array(
        'salad' => 'italian',
        'salad2' => 'ranch',
        'salad3' => 'sesame',
        'salad4' => 'bluecheese'
    ),

    'Dinner' => array(
        'chicken' => 'grilled',
        'chicken2' => 'baked',
        'chicken3' => 'steamed',
        'chicken4' => 'fried',
        'chicken5' => 'broiled'
    ),

    'Breakfast' => array(
        'pancakes' => 'blueberry',
        'pancakes2' => 'cherry',
        'pancakes3' => 'strawberry',
        'pancakes4' => 'lemon'
    )
);

$newArray = array();

foreach ($meals as $key => $value) {
    $temp = array();
    foreach ($value as $innerKey => $innerValue) {
        $temp[$innerValue] = $innerKey;
    }
    $newArray[$key] = $temp;
}

unset($meals);

基本上，您创建一个新数组并使用数组$meals从头开始构建它。

在PHP中修改多维数组，将键替换为值

4 个答案: