Rails DateTime-NoMethodError（nil：NilClass的未定義方法“ []”）

Question

這是我的模型：

class User < ActiveRecord::Base
has_many :appointments
has_many :doctors, :through => :appointments
end

class Doctor < ActiveRecord::Base
has_many :appointments
has_many :users, :through => :appointments
end

class Appointment < ActiveRecord::Base
belongs_to :doctor
belongs_to :user
end

調用控制器動作的代碼：

$.ajax({
  type: "POST",
  url: "/create",
  data: {
    appointment_date: date,
    doctor_id: "1",
    user_id: "1"
  }

//等}）;

行動：

def create
    @appointment = Appointment.new(:appointment_date => params[:data][:appointment_date], 
        :hairdresser_id => params[:data][:doctor_id], :user_id => params[:data][:user_id])
    if @appointment.save
        flash[:success] = "Welcome!"
        redirect_to @user
    else
        alert("failure!")
    end
end

我得到了這個錯誤：

NoMethodError (undefined method `[]' for nil:NilClass)

我正在使用FullCalendar插件，它以這種格式獲取日期：

Fri Sep 13 2013 12:00:50 GMT-0400 (EDT)

我將該日期保存到datetime字段中的數據庫中。

有任何想法嗎？

Answer 1

進行ajax調用時，可以訪問諸如

params[:appointment_date]
params[:doctor_id]
params[:user_id]

並不是

params[:data][:appointment_date]
params[:data][:doctor_id]
params[:data][:user_id]

由於沒有什么叫做params [：data]的東西，所以給你一個nil類錯誤。

Answer 2

如果它是約會控制器的create action，那么它將是

$.ajax({
  type: "POST",
  url: "/appointments",
  data: {
    appointment_date: date,
    doctor_id: "1",
    user_id: "1"
  }

在創建動作中

def create
    @appointment = Appointment.new({:appointment_date => params['appointment_date'], 
        :hairdresser_id => params['doctor_id'], :user_id => params['user_id]'})
    if @appointment.save
        #YOUR CODE
    else
        #YOUR CODE
    end
end