我们经常拿到一个二维数组出来，会发现结果和自己想要的有些偏差，可能需要根据二维数组里的某个字段对数组分组。
先来看以下数组，
Array ( [0] => Array ( [id] => 1 [wo_id] => 2 [evaluate_id] => 1 [type] => 分组1 [ctime] => 2016-12-02 11:39:34 ) [1] => Array ( [id] => 2 [wo_id] => 31 [evaluate_id] => 2 [type] => 分组1 [ctime] => 2016-12-12 11:39:50 ) [2] => Array ( [id] => 3 [wo_id] => 31 [evaluate_id] => 4 [type] => 分组2 [ctime] => 2016-12-02 11:40:01 ) [3] => Array ( [id] => 4 [wo_id] => 2 [evaluate_id] => 5 [type] => 分组2 [ctime] => 2016-12-07 10:21:40 ) [4] => Array ( [id] => 5 [wo_id] => 2 [evaluate_id] => 3 [type] => 分组2 [ctime] => 2016-12-07 10:21:51 ) [5] => Array ( [id] => 6 [wo_id] => 2 [evaluate_id] => 2 [type] => 分组3 [ctime] => 2016-12-07 10:21:56 ) [6] => Array ( [id] => 7 [wo_id] => 4 [evaluate_id] => 2 [type] => 分组3 [ctime] => 2016-12-07 10:22:10 ) )
这里是一个很典型的例子，如果我希望把 数组中的数据 根据 type（分组） 分开处理，如果不分组，可能循环上会非常冗余，所以有了下面的一个分组函数：
public static function array_group_by($arr, $key)
{
$grouped = [];
foreach ($arr as $value) {
$grouped[$value[$key]][] = $value;
}
// Recursively build a nested grouping if more parameters are supplied
// Each grouped array value is grouped according to the next sequential key
if (func_num_args() > 2) {
$args = func_get_args();
foreach ($grouped as $key => $value) {
$parms = array_merge([$value], array_slice($args, 2, func_num_args()));
$grouped[$key] = call_user_func_array('array_group_by', $parms);
}
}
return $grouped;
}
$arr : 二维数组
$key: 需要分组的key
得到的结果是：
Array ( [分组2] => Array ( [0] => Array ( [id] => 1 [wo_id] => 2 [evaluate_id] => 1 [ctime] => 2016-12-02 11:39:34 [type] => 分组2 ) [1] => Array ( [id] => 2 [wo_id] => 31 [evaluate_id] => 2 [ctime] => 2016-12-12 11:39:50 [type] => 分组2 ) [2] => Array ( [id] => 3 [wo_id] => 31 [evaluate_id] => 4 [ctime] => 2016-12-02 11:40:01 [type] => 分组2 ) ) [分组1] => Array ( [0] => Array ( [id] => 4 [wo_id] => 2 [evaluate_id] => 5 [ctime] => 2016-12-07 10:21:40 [type] => 分组1 ) [1] => Array ( [id] => 5 [wo_id] => 2 [evaluate_id] => 3 [ctime] => 2016-12-07 10:21:51 [type] => 分组1 ) ) )
以上所述是小编给大家介绍的PHP 根据key 给二维数组分组，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对网站的支持！
