educoder/app/models/exercise_question.rb

#encoding: utf-8
class ExerciseQuestion < ApplicationRecord

  belongs_to :exercise
  belongs_to :shixun,  optional: true

  has_many :exercise_choices
  has_many :exercise_answers
  has_many :exercise_shixun_challenges
  has_many :exercise_shixun_answers
  has_many :exercise_answer_comments
  has_many :exercise_standard_answers

  scope :insert_question_ex, lambda {|k| where("question_number > ?",k)}
  scope :find_by_custom, lambda {|k,v| where("#{k} = ?",v)}  #根据传入的参数查找问题
  scope :left_question_choose, lambda {|k,v| where("#{k} > ?",v)}  #根据传入的参数查找问题
  scope :find_objective_questions, -> {where("question_type != ?",4)}  #查找全部客观题
  # scope :next_exercise, lambda {|k| where("question_number > ?",k).first}
  # scope :last_exercise, lambda {|k| where("question_number < ?",k).last}
  after_destroy :destroy_questions_relations

  def destroy_questions_relations
    exercise_choices.destroy_all
    exercise_shixun_challenges.destroy_all
  end

  def question_type_name
    case self.question_type
    when 0
      "单选题"
    when 1
      "多选题"
    when 2
      "判断题"
    when 3
      "填空题"
    when 4
      "简答题"
    when 5
      "实训题"
    end
  end

  #获取问题的全部标准答案
  def get_standard_answer_ids
    exercise_standard_answers.pluck(:exercise_choice_id)
  end

  def get_standard_answer_text
    exercise_standard_answers.pluck(:answer_text)
  end

end