如何使用Laravel（Eloquent的）地图集合函数重构php foreach

Question

I've just watched Adam Wathan's video on Refactoring Loops and Conditionals, and feel like I can use the map collection method in the sumLeagueStats method on my Team model (rather than the foreach).

I have a relationship on teams -> leagues, and the getLeagueStats function gets all of the stats (played, won, drew, lost, for, against, points) from the leagues table for the relevant team.

In the sumLeagueStats method I was going to use a foreach loop and loop through each stat by year, and take the sum of all of the played, etc, and return it, but having watched the above video,

class Team extends Model {

    public function league()
    {
        return $this->hasMany('league');
    }

    public function getLeagueStats($year = [2018])
    {
        return $this->league()->whereIn('year', [$year])->get();
    }

    public function sumLeagueStats($year = [2018])
    {
        foreach {
            ...
            return
        }
        /*
        * Want to return a colleciton with the following:
        *
        $this->getLeagueStats()->sum('played');
        $this->getLeagueStats()->sum('won');
        $this->getLeagueStats()->sum('drew');
        $this->getLeagueStats()->sum('lost');
        $this->getLeagueStats()->sum('for');
        $this->getLeagueStats()->sum('against');
        $this->getLeagueStats()->sum('points');
        */
    }
}

I'm new to Laravel, so firstly want to check. my suspicions are correct, and secondly looking for any insight/resource for more information, as the docs are slightly lacking).

Answer 1

Calling getLeagueStats everytime is making a request to your database everytime you call the sum method, so you can create a variable to work with and create a collection that represents the data :

$stats = $this->getLeagueStats();
return collect([
    'played' => $stats->sum('played'),
    'won' => $stats->sum('won'),
    'drew' => $stats->sum('drew'),
    'won' => $stats->sum('won'),
    'lost' => $stats->sum('lost'),
    'for' => $stats->sum('for'),
    'points' => $stats->sum('points')
]);

is that a what you want ?