识别 2d 数组的行属于 3 个组中的 1 个，并计算每组中的出现次数

Question

我有这个数组：

Array ( 
    [0] => Array ( [countThis_id] => 1 [icon] => add.gif [url] => add.php)
    [1] => Array ( [countThis_id] => 1 [icon] => add.gif [url] => add.php)
    [2] => Array ( [countThis_id] => 2 [icon] => add.gif [url] => add.php)
    [3] => Array ( [countThis_id] => 2 [icon] => add.gif [url] => add.php)
    [4] => Array ( [countThis_id] => 5 [icon] => add.gif [url] => add.php)
    [5] => Array ( [countThis_id] => 6 [icon] => add.gif [url] => add.php)
    [6] => Array ( [countThis_id] => 7 [icon] => add.gif [url] => add.php)
    [7] => Array ( [countThis_id] => 7 [icon] => add.gif [url] => add.php)     
)

我想计算与预定义组相关的 countThis_id 值的出现次数。

• 如果 1，则向 count_1 组总计加 1
• 如果 2，则向 count_2 组总计加 1 ，
• 如果有任何其他值，则向 the_Rest 组总计添加 1。

我想要的结果：

Array ( 
    [0] => Array ( [countThis_id] => 1 [icon] => add.gif [url] => add.php)
    [1] => Array ( [countThis_id] => 1 [icon] => add.gif [url] => add.php)
    [2] => Array ( [countThis_id] => 2 [icon] => add.gif [url] => add.php)
    [3] => Array ( [countThis_id] => 2 [icon] => add.gif [url] => add.php)
    [4] => Array ( [countThis_id] => 5 [icon] => add.gif [url] => add.php)
    [5] => Array ( [countThis_id] => 6 [icon] => add.gif [url] => add.php)
    [6] => Array ( [countThis_id] => 7 [icon] => add.gif [url] => add.php)
    [7] => Array ( [countThis_id] => 7 [icon] => add.gif [url] => add.php)   
    [8] => Array ( [count_1] => 2 [count_2] => 2 [the_Rest] => 4)   
)

Answer 1

$result = array('count_1' => 0, 'count_2'=>0, 'the_Rest'=>0);
foreach($array as $arr){
   if($arr['countThis_id'] == 2){
     $result['count_1']++;
   }
   else if($arr['countThis_id'] == 1){
     $result['count_1']++;
   }
   else {
     $result['the_rest']++;
   }
}

array_push($array, $result);
var_dump($array);

Answer 2

三向比较运算符（又名：“太空船运算符”）返回 -1、0 或 1。您的任务需要将数据识别为三个不同的组。因为您似乎正在评估大于零的整数，并且需要 1、2 和任何其他数字的组，所以您可以将遇到的每个数字与 2 进行比较 并利用映射数组来消除对 if 块的需要。

代码：(演示)

$buckets = [-1 => 'count_1', 0 => 'count_2', 1 => 'the_Rest'];
$totals = array_fill_keys($buckets, 0);
foreach ($array as ['countThis_id' => $id]) {
    ++$totals[$buckets[$id <=> 2]];
}
$array[] = $totals;
var_export($array);

或者类似地，使用 match()。 演示

$totals = ['count_1' => 0, 'count_2' => 0, 'the_Rest' => 0];
foreach ($array as ['countThis_id' => $id]) {
    ++$totals[match ($id) {
        1 => 'count_1',
        2 => 'count_2',
        default => 'the_Rest',
    }];
}
$array[] = $totals;
var_export($array);