按年龄类别分组和计算用户

Question

I'm trying to split users in two categories, younger or older than 20, by looping thru them in order to calculate age value with Carbon.

    public function groupAndCountBasedOnAge($users) {
 // i'm giving the array keys & values
    $ageGroups = array('younger than 20' => 0,
                       'older than 20' => 0); 


foreach($users as $u) {

    $now = Carbon::now();
    $u->age = Carbon::createFromFormat('Y-m-d', $u->birth_date);
    $u->age = $now->diffInYears($u->age);  // getting actual age value for each user

    if($u->age < 20 ) {
        $ageGroups[younger than 20'] += 1;
    }
    elseif($u->age > 20 ) {
        $ageGroups['older than 20'] += 1;
    }

return $ageGroups;

}

}

public function index() {

$users = DB::table('users')->get();

$users = $this->groupAndCountBasedOnAge($users);

return view('/users/list', [
    'users' => $users
]);

} However dd($users) always returns the same array, no matter what I change:

array:2 [▼
  "less than 20" => 1
  "older than 20" => 0
]

Answer 1

You could use the partition() and Count() methods of Laravel Collections.

use Illuminate\Support\Carbon;

//

public function index() {

    $users = DB::table('users')->get();
    $users = $this->groupAndCountBasedOnAge($users);

    return view('/users/list', [
        'users' => $users
    ]);
}

public function groupAndCountBasedOnAge($users)
{
    list($under, $equalOrAbove) = collect($users)->partition(function ($user) {
        return Carbon::now()
            ->diffInYears(Carbon::createFromFormat('Y-m-d', $user->birth_date)) < 20;
    });

    return [
        'underTwenty'  => [
            'users' => $under->all(),
            'count' => $under->count()
        ],
        'equalOrAboveTwenty' => [
            'users' => $equalOrAbove->all(),
            'count' => $equalOrAbove->count()
        ]
    ];
}

---

Note

I've also grouped the users because I guessed you wanted this (acoording to name of your method).