如何在<select>中通过雄辩来分组

I want to have unique mounths in SELECT. I find out i have to use GROUP BY. But it doesnt work this way:

 @foreach($months as $month)
       <option value="{{ $month->id }}">{{ Carbon\Carbon::parse($month
->date)
->format(' F ')
->groupBy('date') }}</option>    
 @endforeach

How to use groupBy in this way? Because it looks like this right now without GROUP BY:

My Laravel Controller:

public function index()
{
    $users = User::all(['name', 'id']);
    $months = RouteInfo::all(['date', 'id']);

    return view('admin.index', compact('users', $users, 'months', $months));
}

Thank you for your help

You need just filter items before show

@php
$uniqueMonth = [];
  foreach($months as $key=>$month){
     $month = Carbon\Carbon::parse($month->date);
     $uniqueMonth[$month->format('m')] = $month->format(' F ');
  }
  ksort($uniqueMonth); // sorting months
@endphp

@foreach($uniqueMonth as $key=>$month)
   <option value="{{ $key }}">{{ $month }}</option>
@endforeach

You could do something like this, within your controller.

$months = RouteInfo::all(['date', 'id'])->groupBy(function($month) {
    return Carbon::parse($month->date)->format('F');
});

Then within your view

@foreach($months as $month)
    <option>{{ $month }}</option>
@endforeach

This is untested, please let me know if it works for you or if there are any errors.