在rails中加入table；多对多；尝试在实例上调用 join 方法

Question

我几个小时前刚刚做了这个，现在我无法让它在第二次尝试中工作。有很多用户和很多事件目标。 Users have many EventGoals and EventGoals have many Users，两者都通过加入table称为EventGoalClaims。 @event_goal 正确通过，但我得到一个 `

undefined method `event_goal_claims' for #<EventGoal:0x007fd11b0ce178>`

视图如下（第一行出错）：

<%= form_for([@event_goal, @event_goal.event_goal_claims.build]) do |f| %>
  <%= f.hidden_field :user_id, :value =>  current_user.id %>
  <%= f.hidden_field :user_last_name, :value =>  current_user.last_name %>

控制器

  def create
        @event_goal = EventGoal.find(params[:event_goal_id])
        @event_goal_claim = @event_goal.event_goal_claims.build(eventgoalclaim_params)
          @event_goal_claim.event_goal_id = @event_goal.id
          @event_goal_claim.user_id = current_user.id
          @event_goal_claim.user_last_name = current_user.last_name

...

 private
  def eventgoalclaim_params
    params.require(:event_goal_claim).permit(:event_goal_id, :user_id, :user_last_name, :approved)
  end

编辑

class EventGoal < ActiveRecord::Base
    belongs_to :event
    has_many :users, through: :event_goal_claims
end

Answer 1

答案可能在于三个模型之一的关联。确保它们看起来像这样：

user.rb
Class User < ActiveRecord::Base
  has_many :event_goal_claims
  has_many :event_goals, through: :event_goal_claims

event_goal.rb
Class EventGoal < ActiveRecord::Base
  has_many :event_goal_claims
  has_many :users, through: :event_goal_claims

event_goal_claim.rb
Class EventGoalClaim < ActiveRecord::Base
  belongs_to :user
  belongs_to :event_goal

还值得注意：这都是假设您的数据库在 schema.rb 中的 event_goal_claims table 上有外键标记为 user_id and event_goal_id。如果它们与此不同，您将需要在模型的关联中明确说明外键的名称。

在rails中加入table；多对多；尝试在实例上调用 join 方法

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