我有以下数组，其中每个项目可能（也可能不依赖）另一个：
$test = array(
'c' => array(
'depends' => array('b')
),
'a' => array(),
'b' => array(
'depends' => array('a', 'd')
),
'd' => array(
'depends' => array('a')
)
);
我想要的输出结果
$test = array(
'a' => array(),
'd' => array(
'depends' => array('a')
),
'b' => array(
'depends' => array('a', 'd')
),
'c' => array(
'depends' => array('b')
)
);
这段代码的问题类似于这个问题"如何重新排列数组项，在顶部移动依赖项？"
但有不同的是，如果依赖有多个依赖函数array_multi-sort无法对其进行排序。
我想这就是你想要的，尽管你的问题很模糊：
<?php
$input = array(
'c' => array(
'depends' => array('b')
),
'a' => array(),
'b' => array(
'depends' => array('a', 'd')
),
'd' => array(
'depends' => array('a')
)
);
$output = array();
foreach ($input as $dependant=>$settings) {
if ( is_array($settings)
&& isset($settings['depends'])
&& is_array($settings['depends'])) {
foreach ($settings['depends'] as $dependent) {
$output[$dependent]['dependent'][] = $dependant;
}
}
}
var_dump($output);
输出为：
array(3) {
'b' =>
array(1) {
'dependent' =>
array(1) {
[0] =>
string(1) "c"
}
}
'a' =>
array(1) {
'dependent' =>
array(2) {
[0] =>
string(1) "b"
[1] =>
string(1) "d"
}
}
'd' =>
array(1) {
'dependent' =>
array(1) {
[0] =>
string(1) "b"
}
}
}
<?php
$test = array(
'c' => array(
'depends' => array('b')
),
'a' => array(),
'b' => array(
'depends' => array('a', 'd')
),
'd' => array(
'depends' => array('a')
)
);
$rearranged = array();
$test_left = $test;
do {
$resolved = false; // Check for rounds without any move
reset($test_left);
while (list($key, $val) = each($test_left)) {
$move = false;
if (isset($val['depends']) && !empty($val['depends'])) {
// Dependencies count must be not greater than rearranged array length
$depends = count($val['depends']) <= count($rearranged);
// All dependencies must be set in rearranged array already
while ($depends && (list(, $dep_key) = each($val['depends']))) {
if (!array_key_exists($dep_key, $rearranged)) {
$depends = false;
}
}
$move = $depends;
} else {
// Independent items moves to top
$move = true;
}
if ($move) {
$rearranged[$key] = $val;
unset($test_left[$key]);
$resolved = true;
}
}
}
while ($resolved && !empty($test_left));
if (empty($test_left)) {
echo 'Success<pre>';
print_r($rearranged);
echo '</pre>';
} else {
echo 'There are some unresolved dependencies';
}