表"人"+----+------------+-------+|锡 |姓名 |鞋面 |+----+------------+-------+| 1 |克莱门特 | 0 || 2 |吉恩 | 1 || 3 |安妮 | 1 || 4 |袁 | 2 || 5 |梅 | 2 || 6 |蓝色 | 3 || 7 |杨 | 5 || 8 |洛琳达 | 0 |+----+------------+-------+
结构是这样的:
克莱门特 珍 元 美 阳 安妮 蓝洛琳达
upper
列说明了他/她自己的上位人。
问题是:如何从 MySQL 获取嵌套/多维数组?我以为我可以使用循环来获取,但我未能自动获取所有低音。数组可以是这样的:
数组( [1]=>数组 ( [自我]=>克莱门特 [2]=>数组 ( [自我]=>让 [4]=>数组 ( [自我]=>元 ) [5]=>数组 ( [自我]=>美 [7]=>数组 ( [自我]=>阳 ) ) ) [3]=>数组 ( [自我]=>安妮 [6]=>数组 ( [自我]=>蓝色 ) ) ) [8]=>数组 ( [自我]=>洛琳达 ))
由于我们不知道一个人有多少"上层"人员,因此解决方案应该是一个自动化功能,可以构建一个完整的阵列,而不仅仅是三维或四维。换句话说,该功能应该从高层深入到所有下层的人。
给定您的输入:
$input = array(
array('sn' => 1, 'name' => 'Clement', 'upper' => 0),
array('sn' => 2, 'name' => 'Jean', 'upper' => 1),
array('sn' => 3, 'name' => 'Annie', 'upper' => 1),
array('sn' => 4, 'name' => 'Yuan', 'upper' => 2),
array('sn' => 5, 'name' => 'Mei', 'upper' => 2),
array('sn' => 6, 'name' => 'Blue', 'upper' => 3),
array('sn' => 7, 'name' => 'Yang', 'upper' => 5),
array('sn' => 8, 'name' => 'Lorinda', 'upper' => 0),
);
使用引用,您可以使用以下循环构建树:
$map = array();
foreach ($input as $node) {
// init self
if (!array_key_exists($node['sn'], $map)) {
$map[$node['sn']] = array('self' => $node['name']);
}
else {
$map[$node['sn']]['self'] = $node['name'];
}
// init parent
if (!array_key_exists($node['upper'], $map)) {
$map[$node['upper']] = array();
}
// add to parent
$map[$node['upper']][$node['sn']] = & $map[$node['sn']];
}
print_r($map[0]);
演示:http://3v4l.org/vuVPu
假设数据是这样的
$data = array(
array(1, 'Clement', 0),
array(2, 'Jean ', 1),
array(3, 'Annie ', 1),
array(4, 'Yuan ', 2),
array(5, 'Mei ', 2),
array(6, 'Blue ', 3),
array(7, 'Yang ', 5),
array(8, 'Lorinda', 0),
);
此递归函数可能有效:
function tree($data, $node) {
foreach($data as $e)
if($e[2] == $node[0])
$node['children'] []= tree($data, $e);
return $node;
}
像这样使用它:
$tree = tree($data, array(0));
print_r($tree);
使用参考地图
$input = array(
array('sn' => 1, 'name' => 'Clement', 'upper' => 0),
array('sn' => 2, 'name' => 'Jean', 'upper' => 1),
array('sn' => 3, 'name' => 'Annie', 'upper' => 1),
array('sn' => 4, 'name' => 'Yuan', 'upper' => 2),
array('sn' => 5, 'name' => 'Mei', 'upper' => 2),
array('sn' => 6, 'name' => 'Blue', 'upper' => 3),
array('sn' => 7, 'name' => 'Yang', 'upper' => 5),
array('sn' => 8, 'name' => 'Lorinda', 'upper' => 0),
);
$map = []; // map a reference by id for each item
foreach ($input as &$inp) {
$map[$inp['sn']] = &$inp;
}
foreach ($map as &$_inp) { // assign each item to its parent, with help of the map
if ($_inp['upper']) {
$map[$_inp['upper']]['children'] = &$map[$_inp['upper']]['children'] ?? [];
$map[$_inp['upper']]['children'][] = &$_inp;
}
}
$result = array_filter($map, fn($item) => !$item['upper']);
print_r($result);```