在集合 laravel 中使用查询范围

发布于01月24日

My Association model looks like this (irrelevant code redacted):

class Association extends Model
{
    public function members() {
        return $this->hasMany('App\Member');
    }

}

我的会员模式如下所示:

class Member extends Model
{
    public function scopeActive($query) {
        return $query->where('membership_ended_at', Null);
    }
    public function scopeInactive($query) {
        return $query->whereNotNull('membership_ended_at');
    }
}

这就是我希望能够做到的:

$association = Association::find(49);
$association->members->active()->count();

Now, I'm aware there's a difference between a Query and a Collection. But what I'm basically asking is if there's some kind of similar scope for collections. Of course, the optimal solution would be to not have to write TWO active methods, but use one for both purposes.

推荐答案

(问题已在 comments 中得到回答，但不妨写一个恰当的答案)

不可能在Colletion中使用查询作用域，因为查询作用域是口才中用于向数据库查询添加约束的概念，而Collections只是事物(数据、对象等)的集合.

In your case, what you need to do is to change this line:

$association->members->active()->count();

to:

$association->members()->active()->count();

This works because when we call members as a method, we are getting a QueryBuilder instance, and with that we can start chaining scopes to the query before calling the count method.