Question

我有点困惑，为什么我收到这个错误，因为（我认为）这表明我的current_customer返回nil。我不知道如何解决这个问题，我的current_customer方法，会话控制器或我的events_controller是一个问题......

活动模型：

uint WS_POPUP = 0x80000000;

protected override CreateParams CreateParams
{
    get
    {
        CreateParams createParams = base.CreateParams;
        createParams.Style |= unchecked((int)WS_POPUP);
        return createParams;
    }
}

事件控制器：

class Event < ActiveRecord::Base
  belongs_to :calendar

end

客户模式：

class EventsController < ApplicationController

  def new
    @event = Event.new
    @calendar = current_customer.calendar #WHY IS IT NOT ERRORING HERE TOO?

  end


  def create

    **@calendar = current_customer.calendar #IT IS CALLING ERROR HERE**
    @event = @calendar.build.event(event_params)
    if @event.save
      redirect_to '/main'
    else
      redirect_to '/compose'
    end
  end


  private
  def event_params
    params.require(:event).permit(:calendar_id, :name, :starts_at, :ends_at) 
  end

客户控制人：

class Customer < ActiveRecord::Base
  belongs_to :business
  has_one :calendar

  has_secure_password

  attr_accessor :remember_token

  #remembers a user in the database for  use in persistent sessions
  def remember
    self.remember_token = Customer.new_token
    update_attribute(:remember_digest, Customer.digest(remember_token))
  end

  def Customer.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
        BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end

  def forget
    update_attribute(:remember_digest, nil)
  end

  def Customer.new_token
    SecureRandom.urlsafe_base64
  end

  #returns true if the given token matches the digest
  def authenticated?(remember_token)
    BCrypt::Password.new(remember_digest).is_password?(remember_token)
  end


end

会话控制器：

class CustomersController < ApplicationController

  def new

    @customer = Customer.new
    @businesses = Business.all
    @calendar = Calendar.new

  end

  def create

    @customer = Customer.create(customer_params)

    @calendar = @customer.build_calendar
    @customer.save!
    session[:customer_id] = @customer.id

    redirect_to '/'
  rescue ActiveRecord::RecordInvalid => ex
    render action: 'new', alert: ex.message
  end

  private
  def customer_params
    params.require(:customer).permit(:first_name, :last_name, :business_no, :email, :password, :business_id)
  end

end

application.controller中的Current_customer方法：

class SessionsController < ApplicationController

  def new

  end

  def create
    @customer = Customer.find_by_email(params[:session][:email])
    if @customer && @customer.authenticate(params[:session][:password])
      session[:customer_id] = @customer.id #log in
      @customer.remember
      cookies.permanent.signed[:customer_id] = @customer.id
      cookies.permanent[:remember_token] = @customer.remember_token
      redirect_to '/main'
    else
      #need to add flash error: invalid password/email combination
      redirect_to '/login'
    end
  end

  def destroy
    @current_customer.forget
    cookies.delete(:customer_id)
    cookies.delete(:remember_token)
    session.delete(:customer_id)
    @current_customer = nil
    redirect_to '/'
  end
end

日历模型：

helper_method :current_customer

  def current_customer
    if (customer_id = session[:customer_id])
      @current_customer ||= Customer.find_by(id: customer_id)
    elsif (customer_id = cookies.signed[:customer_id])
      customer = Customer.find_by(id: customer_id)
      if customer && customer.authenticated?(cookies[:remember_token])
        session[:customer_id] = customer.id #log in
        @current_customer = customer

      end
    end
  end

calendars_controller：

class Calendar < ActiveRecord::Base
  belongs_to :customer
  has_many :events

end

我是Ruby / Rails的新手，所以我非常感谢任何解释和答案，请帮忙！感谢

Answer 1

@calendar = current_customer.calendar
@event = @calendar.build.event(event_params)

根据错误消息，@calendar为nil，因此当您在下一行中致电@calendar.build.event(event_params)时，它会调用：nil.build，因此您会收到错误消息。

出于某种原因，您的current_customer calendar nil对于该请求是current_customer。想出来并确保calendar在数据库中存在@event = @calendar.build.event(event_params)，那么它应该有效。

此外，您需要更改：

@event = @calendar.events.build(event_params)

要：

suppressEvent

Answer 2

似乎@calendar在事件控制器中是零。

首先检查current_customer会将您期望的客户转回给客户。

然后检查current_customer是否创建了一个日历供您参考。

EventsController＃中的NoMethodError为nil创建未定义的方法`build'：NilClass？

2 个答案: