它是可能的,在PHP中,在不使用递归或引用的情况下扁平化(bi/multi)维数组?
我只对值感兴趣,所以键可以忽略,我认为在array_map()和array_values()的行。
它是可能的,在PHP中,在不使用递归或引用的情况下扁平化(bi/multi)维数组?
我只对值感兴趣,所以键可以忽略,我认为在array_map()和array_values()的行。
当前回答
因为这里的代码看起来很可怕。下面是一个将多维数组转换为html格式兼容语法的函数,但它更容易阅读。
/**
* Flattens a multi demensional array into a one dimensional
* to be compatible with hidden html fields.
*
* @param array $array
* Array in the form:
* array(
* 'a' => array(
* 'b' => '1'
* )
* )
*
* @return array
* Array in the form:
* array(
* 'a[b]' => 1,
* )
*/
function flatten_array($array) {
// Continue until $array is a one-dimensional array.
$continue = TRUE;
while ($continue) {
$continue = FALSE;
// Walk through top and second level of $array and move
// all values in the second level up one level.
foreach ($array as $key => $value) {
if (is_array($value)) {
// Second level found, therefore continue.
$continue = TRUE;
// Move each value a level up.
foreach ($value as $child_key => $child_value) {
$array[$key . '[' . $child_key . ']'] = $child_value;
}
// Remove second level array from top level.
unset($array[$key]);
}
}
}
return $array;
}
其他回答
因为这里的代码看起来很可怕。下面是一个将多维数组转换为html格式兼容语法的函数,但它更容易阅读。
/**
* Flattens a multi demensional array into a one dimensional
* to be compatible with hidden html fields.
*
* @param array $array
* Array in the form:
* array(
* 'a' => array(
* 'b' => '1'
* )
* )
*
* @return array
* Array in the form:
* array(
* 'a[b]' => 1,
* )
*/
function flatten_array($array) {
// Continue until $array is a one-dimensional array.
$continue = TRUE;
while ($continue) {
$continue = FALSE;
// Walk through top and second level of $array and move
// all values in the second level up one level.
foreach ($array as $key => $value) {
if (is_array($value)) {
// Second level found, therefore continue.
$continue = TRUE;
// Move each value a level up.
foreach ($value as $child_key => $child_value) {
$array[$key . '[' . $child_key . ']'] = $child_value;
}
// Remove second level array from top level.
unset($array[$key]);
}
}
}
return $array;
}
非递归,非基于引用的实现,这可能比基于递归的实现更容易理解。 可以管理任意深度多维数组,不能平化关联数组。 它的工作原理是每个周期将数组压平一层,直到它完全有效。
function array_flatten(): array{
$result = func_get_args();
// check all elements of $list are not arrays
$_is_flat = function (array $list): bool {
foreach ($list as $val) {
if (is_array($val)) {
return false;
}
}
return true;
};
do {
$tmp = [];
foreach ($result as $val) {
if (is_array($val)) {
if (!array_is_list($val)) {
throw new \Exception(sprintf("array_flatten can't handle associative arrays: %s", json_encode($val)));
}
$tmp = array_merge($tmp, $val);
} else {
$tmp[] = $val;
}
}
$result = $tmp;
} while (!$_is_flat($result));
return $result;
}
以下是它处理的情况:
assertEquals(array_flatten(1, 2), $expected = [1, 2], 'array_flatten 1a');
assertEquals(array_flatten([1], [2]), $expected = [1, 2], 'array_flatten 1b');
assertEquals(array_flatten([1], [[2], 3]), $expected = [1, 2, 3], 'array_flatten 1c');
assertEquals(array_flatten(1, [2, 3], [4, 5]), $expected = [1, 2, 3, 4, 5], 'array_flatten 2');
assertEquals(array_flatten(2, 3, [4, 5], [6, 7], 8), $expected = [2, 3, 4, 5, 6, 7, 8], 'array_flatten 3');
assertEquals(array_flatten([2, 3, [4, 5], [6, 7], 8]), $expected = [2, 3, 4, 5, 6, 7, 8], 'array_flatten 4');
assertEquals(array_flatten([2, [3, [4, [5]], [6, [7]], 8]]), $expected = [2, 3, 4, 5, 6, 7, 8], 'array_flatten complex');
从PHP 5.3开始,最短的解决方案似乎是array_walk_recursive()与新的闭包语法:
function flatten(array $array) {
$return = array();
array_walk_recursive($array, function($a) use (&$return) { $return[] = $a; });
return $return;
}
/**
* For merging values of a multidimensional array into one
*
* $array = [
* 0 => [
* 0 => 'a1',
* 1 => 'b1',
* 2 => 'c1',
* 3 => 'd1'
* ],
* 1 => [
* 0 => 'a2',
* 1 => 'b2',
* 2 => 'c2',
* ]
* ];
*
* becomes :
*
* $array = [
* 0 => 'a1',
* 1 => 'b1',
* 2 => 'c1',
* 3 => 'd1',
* 4 => 'a2',
* 5 => 'b2',
* 6 => 'c2',
*
* ]
*/
array_reduce
(
$multiArray
, function ($lastItem, $currentItem) {
$lastItem = $lastItem ?: array();
return array_merge($lastItem, array_values($currentItem));
}
);
依据片段
试试下面这个简单的函数:
function _flatten_array($arr) {
while ($arr) {
list($key, $value) = each($arr);
is_array($value) ? $arr = $value : $out[$key] = $value;
unset($arr[$key]);
}
return (array)$out;
}
所以从这里:
array (
'und' =>
array (
'profiles' =>
array (
0 =>
array (
'commerce_customer_address' =>
array (
'und' =>
array (
0 =>
array (
'first_name' => 'First name',
'last_name' => 'Last name',
'thoroughfare' => 'Address 1',
'premise' => 'Address 2',
'locality' => 'Town/City',
'administrative_area' => 'County',
'postal_code' => 'Postcode',
),
),
),
),
),
),
)
你会得到:
array (
'first_name' => 'First name',
'last_name' => 'Last name',
'thoroughfare' => 'Address 1',
'premise' => 'Address 2',
'locality' => 'Town/City',
'administrative_area' => 'County',
'postal_code' => 'Postcode',
)