时间：2021-03-28 09:18:22 | 栏目：PHP代码 | 点击：次
要求：
将二维数组$arr转换为以‘time'和‘type'为下标、‘data‘为值的二维数组；
原数组：
$arr = array(
0 => array(
'data' => 100,
'type' => 1,
'time' => '2018-01-26',
),
1 => array(
'data' => 200,
'type' => 2,
'time' => '2018-01-26',
),
2 => array(
'data' => 300,
'type' => 2,
'time' => '2018-01-27',
),
3 => array(
'data' => 400,
'type' => 3,
'time' => '2018-01-27',
),
4 => array(
'data' => 500,
'type' => 4,
'time' => '2018-01-28',
),
);
转换：
foreach ($arr as $key => $value) {
$change[$value['time']][$value['type']] = $value['data'];
}
结果：
array(3) {
["2018-01-26"] => array(2) {
[1] => int(100)
[2] => int(200)
}
["2018-01-27"] => array(2) {
[2] => int(300)
[3] => int(400)
}
["2018-01-28"] => array(1) {
[4] => int(500)
}
}