用户提交答卷后，给出得分

app/controllers/exercise_controller.rb

@@ -190,9 +190,9 @@ class ExerciseController < ApplicationController
     @exercise_question.question_score = params[:question_score]
     ################处理选项
     if params[:question_answer]
-      # @exercise_question.exercise_choices.each do |answer|
-      #   answer.destroy unless params[:question_answer].keys.include? answer.id.to_s
-      # end
+      @exercise_question.exercise_choices.each do |answer|
+        answer.destroy unless params[:question_answer].keys.include? answer.id.to_s
+      end
       # 界面需要判断选择题至少有一个选项
       for i in 1..@exercise_question.exercise_choices.count
         question = @exercise_question.exercise_choices.find_by_id params[:question_answer].keys[i-1]
@@ -265,9 +265,10 @@ class ExerciseController < ApplicationController
     end
   end
 
-  # 学生提交答卷
+  # 学生提交答卷，选着答案的课程中提交
   def commit_answer
-    eq = ExerciseQuestion.find(params[:poll_question_id])
+    eq = ExerciseQuestion.find(params[:exercise_question_id])
+    # 已提交过的则不允许答题
     if has_commit_exercise?(@exercise.id,User.current.id) && (!User.current.admin?)
       render :json => {:text => "failure"}
       return
@@ -369,11 +370,12 @@ class ExerciseController < ApplicationController
     # 老师不需要提交
     if User.current.allowed_to?(:as_teacher,@course)
       redirect_to exercise_url(@exercise)
+      # REDO: 提示提交成功
     else
       # 答题过程中需要统计完成量
       @uncomplete_question = get_uncomplete_question(@exercise, User.current)
       # 获取改学生的考试得分
-      score = get_answer_score(@exercise)
+      score = calculate_student_score(@exercise, User.current)
       if @uncomplete_question.count < 1
         # 查看是否有已提交记录
         eu = get_exercise_user(@exercise.id, User.current.id)
@@ -395,6 +397,26 @@ class ExerciseController < ApplicationController
     end
   end
 
+  # 计算学生得分
+  def calculate_student_score(exercise, user)
+    score = 0
+    exercise_qustions = exercise.exercise_questions
+    exercise_qustions.each do |question|
+      answer = get_user_answer(question, user)
+      standard_answer = get_user_standard_answer(question, user)
+      # 问答题有多个答案
+      if question.question_type == 3
+        if standard_answer.exercise_choice_id.include?(answer.exercise_choice_id)
+          score = score + question.question_score
+        end
+      else
+        if answer.exercise_choice_id == standard_answer.exercise_choice_id
+          score = score + question.question_score
+        end
+      end
+    end
+    score
+  end
 
   private
   # ExerciseUser记录用户是否已提交问卷有对应的记录则已提交，没有则新建一个
@@ -419,12 +441,18 @@ class ExerciseController < ApplicationController
     uncomplete_question
   end
 
-  # 获取问题的答案
+  # 获取当前学生回答问题的答案
   def get_user_answer(question,user)
     user_answer = question.exercise_answers.where("#{ExerciseAnswer.table_name}.user_id = #{user.id}")
     user_answer
   end
 
+  # 获取问题的标准答案
+  def get_user_standard_answer(question,user)
+    standard_answer = question.exercise_standard_answers
+    standard_answer
+  end
+
   # 是否完成了答题
   def get_complete_question(exercise,user)
     questions = exercise.exercise_questions