Question

我在rails中做了一个网页，驱动程序可以选择一个公共汽车站，我有模型driver.rb，reservation.rb和sections.rb。当司机观看预订列表时，我希望他能够看到该部分的名称。我使用委托方法来使用节名称。问题是我想在名称中分配属性loc_dep和loc_arr的值（两者都是字符串）。这是代码：

driver.rb

class Driver < ActiveRecord::Base
    before_save { self.email = email.downcase }
    has_many :reservations
    has_secure_password
    attr_accessible :name, :surname, :address, :birth_date, :id,
                    :email, :password, :password_confirmation
    validates_uniqueness_of :email
    validates :password, :length => { :minimum => 5 } , length: { maximum: 20 }
    validates :name, presence: true, length: { maximum: 20 }
    validates :surname, presence: true, length: { maximum: 20 }
    validates :email, presence: true, length: { maximum: 50 }, uniqueness: { case_sensitive: false }
    validates :birth_date, presence: true              
end

reservation.rb

class Reservation < ActiveRecord::Base
    belongs_to :driver
    belongs_to :section
    belongs_to :leaving
    attr_accessible :id, :date, :section_id, :driver_id, :leaving_id
    delegate :name, :to => :driver, prefix: true, :allow_nil => false
    delegate :name, :to => :section, prefix: true, :allow_nil => false
end

section.rb

class Section < ActiveRecord::Base
    self.inheritance_column = nil
    has_many :reservations
    has_many :stops
    has_one :leaving
    attr_accessible :id, :loc_dep, :loc_arr, :type, :time, :leaving_id, :name
    validates :type, inclusion: { in: %w(weekday holiday daily scholastic)} , :allow_nil => false
    validates :loc_dep, presence: true
    validates :loc_arr, presence: true
    validates :time, presence: true
    def as_field 
        "#{loc_dep} - #{loc_arr} (#{type} - #{time} min)"
    end 
end

reservation_controller.rb

class ReservationsController < ApplicationController
  before_action :set_reservation, only: [:show, :edit, :update, :destroy]

  # GET /reservations
  # GET /reservations.json
  def index
    if current_driver.admin
        @reservations = Reservation.all
    else
        @reservations = current_driver.reservations
    end 
  end

  # GET /reservations/1
  # GET /reservations/1.json
  def show
  end

  # GET /reservations/new
  def new
    @reservation = Reservation.new
  end

  # GET /reservations/1/edit
  def edit
   @sections=Section.all
  end

  # POST /reservations
  # POST /reservations.json
  def create
    @reservation = current_driver.reservations.build(reservation_params)
    respond_to do |format|
      if @reservation.save
        format.html { redirect_to @reservation, notice: 'Reservation was successfully created.' }
        format.json { render :show, status: :created, location: @reservation }
      else
        format.html { render :new }
        format.json { render json: @reservation.errors, status: :unprocessable_entity }
      end
    end
  end

  # PATCH/PUT /reservations/1
  # PATCH/PUT /reservations/1.json
  def update
    respond_to do |format|
      if @reservation.update(reservation_params)
        format.html { redirect_to @reservation, notice: 'Reservation was successfully updated.' }
        format.json { render :show, status: :ok, location: @reservation }
      else
        format.html { render :edit }
        format.json { render json: @reservation.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /reservations/1
  # DELETE /reservations/1.json
  def destroy
    @reservation.destroy
    respond_to do |format|
      format.html { redirect_to reservations_url, notice: 'Reservation was successfully destroyed.' }
      format.json { head :no_content }
    end
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_reservation
      @reservation = Reservation.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    private
    def reservation_params
      params.require(:reservation).permit(:date, :section_id)
    end
end

例如： Section（loc_dep =“New York”，loc_arr =“Boston”，type =“scholastic”，time =“50”）---＆gt;所有值都由驱动程序选择

我希望名称的值为“纽约 - 波士顿”。

Answer 1

不确定我是否理解这里的整个问题，但您可以从Section模式中删除“name”，只需使用方法来推断该值：

#Section.rb
def name
  "#{loc_dep} - #{loc_arr}"
end

Rails为变量赋值

1 个答案: