I am using Laravel 5.2 ， How to write the controller of this questionnaire demo below:
There are 3 tables, respondents,sports, they have a "many-to-many" relationship,another one is sport_respondent,which is the relational table of the former two.
respondents
id name email
sports
id sport_name
1 Basketball
2 Football
3 Table tennis
4 Badminton
5 Baseball
6 Swimming
sport_respondent
id respondent_id sport_id
view：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<meta http-equiv="x-ua-compatible" content="ie=edge">
<link href="//cdn.bootcss.com/bootstrap/4.0.0-alpha.2/css/bootstrap.min.css" rel="stylesheet">
<link href="//cdn.bootcss.com/tether/1.3.2/css/tether.min.css" rel="stylesheet">
</head>
<body>
<div class="container">
<form>
<fieldset class="form-group">
<label for="name">Name</label>
<input type="text" class="form-control" id="name" name="name" placeholder="">
</fieldset>
<fieldset class="form-group">
<label for="email">Email</label>
<input type="email" class="form-control" id="email" name="email" placeholder="">
</fieldset>
<div class="checkbox row">
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport1" name="sport[]" value="1">Basketball
</label>
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport2" name="sport[]" value="2">Football
</label>
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport3" name="sport[]" value="3">Table tennis
</label>
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport4" name="sport[]" value="4">Badminton
</label>
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport5" name="sport[]" value="5">Baseball
</label>
<label class="checkbox-inline col-xs-3">
<input type="checkbox" id="sport6" name="sport[]" value="6">Swimming
</label>
</div>
<button type="submit" class="btn btn-primary">Submit</button>
</form>
</div>
<script src="//cdn.bootcss.com/jquery/2.2.3/jquery.min.js"></script>
<script src="//cdn.bootcss.com/tether/1.3.2/js/tether.min.js"></script>
<script src="//cdn.bootcss.com/bootstrap/4.0.0-alpha.2/js/bootstrap.min.js"></script>
</body>
</html>
**Question：**How to write the controller below？
public function store(Request $request)
{
$respondent= new Respondent;
$respondent->name = $request->name;
$respondent->email = $request->email;
$respondent->save();
$sport = new Sport;
//how to write here？
return redirect()->action('RespondentController@index');
}
edit:
this is the new store method according to @AlexeyMezenin ,
public function store(Request $request)
{
$respondent= new Respondent;
$respondent->name = $request->name;
$respondent->email = $request->email;
$respondent->sports()->attach($request->sports);
$respondent->save();
return redirect()->action('RespondentController@index');
}
there is an infomation when running it,
SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'respondent_id' cannot be null (SQL: insert into `sport_respondent` (`respondent_id`, `sport_id`) values (, 1))
it shows that respondent_id is needed,I don't know how to add it,some help please.
I guess you want to use attach() method:
$respondent->sports()->attach($request->sports);
If you have setup relations correctly and $request->sports contains an array of sport IDs, this will work.