Add parameter to submit form laravel - laravel

Question

here you can see my form where I put in a username and have a hidden idgroup field.
{!! Form::open(array('route'=>'create.invitation')) !!}
<div class="form-group">
{{Form::label('username', 'Username')}}
{{Form::text('username', '', ['class' => 'form-control', 'placeholder' => 'Enter Username'])}}
<input type="hidden" name="idgroup" value="{{$group}}"/>
{{ csrf_field() }}
</div>
<div>
{{Form::submit('Submit',['class' => 'btn btn-primary'])}}
<a class="btn btn-default btn-close" href="{{ route('home') }}">Cancel</a>
</div>
{!! Form::close() !!}
After that this route leads me to my controller function
Route::post('invitation/show', 'InvitationController#create')->name('create.invitation');
How can I add the username and the idgroup to my url?
My problem is now when I click submit I get back this url http://127.0.0.1:8000/invitation/create and when I click enter to the url line I get an error no message because no parameter will pass to the function.
Add. Here is the function
public function create(Request $request)
{
$request->validate([
'username' => [
'required', 'alpha_num', new ExistingUser, new UserNotAdmin
]
]);
$username = $request->username;
$iduser = User::where('name', $username)->select('id')->first();
$group = $request->idgroup;
return view('invitation.overview')->with('group', $group)->with('iduser', $iduser);
}

Answer 1

You cannot pass parameter inside POST body without submitting a form.
But you can try to allow both GET or POST by using any() for the route, so you can test the page around.
Route::any('invitation/show', 'InvitationController#create')->name('create.invitation');
And then, you can try pass variable through queries inside URL
http://127.0.0.1:8000/invitation/create?username=something&idgroup=1