python - 测验系统模型 字段选择

Question

我正在 Django 中为测验系统创建一个模型。每个问题有一个问题和 5 个选项。

    class Question(models.Model):
      quiz_question=models.CharField(max_length=1000)
      option1=models.CharField(max_length=500)
      option2=models.CharField(max_length=500)  
      option3=models.CharField(max_length=500)
      option4=models.CharField(max_length=500)
      option5=models.CharField(max_length=500)

这里只有一个答案是正确的答案。哪种是在这里表示答案的最佳方式？是通过添加另一个字段还是可以通过编辑现有字段来完成？

Answer 1

几个月前，我有一个基于问题系统的类似 django 项目。就您而言，我认为您需要创建一个新的 Answer 模型，将 ForeignKey 添加到 Question 模型。

这是我的models.py:

from django.db import models
from django.contrib.auth.models import User
from django.core.urlresolvers import reverse
from django.db.models import (Q, Count, Sum)
from django.utils.translation import ugettext, ugettext_lazy as _
from django.utils.encoding import python_2_unicode_compatible


class TimeStampedModel(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)

    class Meta:
        abstract = True


class QuestionQuerySet(models.QuerySet):

    def published(self):
        return self.filter(publish=True)


@python_2_unicode_compatible
class Question(TimeStampedModel):
    title = models.CharField(max_length=200)
    TYPE_CHOICES = (
        ('short', _('Sort')),
        ('medium', _('Medium')),
        ('complete', _('Complete'))
    )
    type = models.CharField(
        max_length=200,
        choices=TYPE_CHOICES,
        default='short'
    )
    weight = models.PositiveIntegerField()
    publish = models.BooleanField(default=True)
    objects = QuestionQuerySet.as_manager()

    def __str__(self):
        return self.title

    @property
    def total_score(self):
        answer = Answer.objects.filter(
            question__pk=self.pk
        ).annotate(Sum('score'))
        return answer  # .count()

    def get_answers(self):
        return Answer.objects.filter(
            question__pk=self.pk
        )
    get_answers.allow_tags = True

    class Meta:
        verbose_name = _('Detail Question')
        verbose_name_plural = _('Questions')
        ordering = ['-created']


@python_2_unicode_compatible
class Answer(models.Model):
    question = models.ForeignKey(
        Question, related_name='question_answer'
    )
    answer = models.CharField(max_length=200)
    score = models.PositiveIntegerField()


def key_generator():
    import uuid
    key = uuid.uuid4().hex
    if BaseAnswerUser.objects.filter(key=key).exists():
        return "{0}-{1}".format(key, uuid.uuid4().hex)
    return key


@python_2_unicode_compatible
class BaseAnswerUser(TimeStampedModel):
    """
    To save the answers that already answered by user.
    in this case, is such as session method.
    """
    user = models.ForeignKey(
        User, related_name='user_answer'
    )
    key = models.CharField(
        max_length=200,
        unique=True,
        default=key_generator
    )

    def get_absolute_url(self):
        return reverse('result', kwargs={'key': self.key})

    def get_answers(self):
        return AnswerUser.objects.filter(
            base_answer__key=self.key
        )

    def __str__(self):
        return _('Result analyze for %(user)s') % {
            'user': self.user.username,
        }

    class Meta:
        verbose_name = _('Base Answer User')
        verbose_name_plural = _('Base Answer Users')
        ordering = ['-created']


@python_2_unicode_compatible
class AnswerUser(TimeStampedModel):
    question = models.ForeignKey(
        Question, related_name='question_answer_user'
    )
    base_answer = models.ForeignKey(
        BaseAnswerUser, related_name='base_answer_user'
    )
    score = models.PositiveIntegerField(
        null=True, blank=True
    )
    text_answer = models.TextField(
        null=True, blank=True
    )

    @property
    def weight(self):
        return self.question.weight

    def __str__(self):
        return _('Result for %(question)s') % {
            'question': self.question
        }

    class Meta:
        verbose_name = _('Detail User Answer')
        verbose_name_plural = _('User Answers')
        ordering = ['-created']

为了处理仪表板 django admin 中的答案，我使用了 admin.TabularInline。欲了解更多，您可以查看此gist

And see also how to handle Django multiple input field values with same name

希望对你有帮助..

<小时/>

更新

我之前的答案是针对动态答案系统的，例如:

1. 问题 A (有 4 个选项答案)

   • a)。选项答案A
   • b).选项答案B
   • c)。选项答案C
   • d)。选项答案D

2. 问题 B (有 3 个选项答案)

   • a)。选项答案A
   • b).选项答案B
   • c)。选项答案C

<小时/>

如果您实现静态答案系统，据我所知:

The Session Answer User is represented as Base Answer User from my previous answer;

[ Question ] -------------------+
 - title       (chr)            |
 - description (chr)            |
 - weight      (int)            |
    |                           |
    |                           |
    |                           |
   \./                         \./
 [ Answer ]               [ Answer User ]
 - fk_question (int)      - fk_question       (int)
 - option_a    (chr)      - fk_session_answer (int)
 - scroe_a     (int)      - score             (int) # save the final score
 - option_b    (chr)           /'\
 - score_b     (int)            |
                                |
                                |
                                |
                      [ Session Answer User ]
                          - fk_user      (int)
                          - session_key  (char:unique)
                          - created      (date)
                                |
                                |
                               \./
                          [ User Model ]
                            - username    (chr)
                            - date_joined (date)

查询集怎么样？

我想查找特定用户和特定 session 的总分的示例。

>>>
>>> session = get_object_or_404(SessionAnswerUser, user=request.user, session_key='key-key-key')
>>> answered_questions = AnswerUser.objects.filter(session_answer=session)
>>>
>>> # Find total scores. eg: {'score__sum': 15}
>>> answered_questions.aggregate(Sum('score'))['score__sum']
15
>>>

如何以及何时使用session_key？

After the User answered all question (create mode), then redirecting to the result page. an example:

@login_required
def save_answers(request):
    """
    This view isn't using django forms, 
    but only handling at the templates and this view.
    Because until now I don't know how to handle it.
    """
    if request.method == 'POST':
        # retrieve all id/pk's from the `questions` (model:Question)
        questions = request.POST.getlist('question')

        # retrieve all id/pk's from the `answers`. (model:Answer)
        answers = [request.POST['answer-{}'.format(q)] for q in questions]

        # saving the session with `key_generator()`, see my previous answer.
        session = SessionAnswerUser.objects.create(user=request.user)
        session.save()

        # Makesure the length of `questions` is same with length of `answers`
        # 1 answer for 1 question
        if len(questions) == len(answers):
            for n in range(len(questions)):
                dict_answer = {
                    'question': Question.objects.get(pk=questions[n]),
                    'session': session, # from latest session above
                    'score': answers[n]
                }
                answered_questions = AnswerUser.objects.create(**dict_answer)
                answered_questions.save()

            # redirecting to the result page.
            return redirect('/result/page', key=session.session_key)

        else:
            # length of `questions` is not same with length of `answers`
            # do stuff...


@login_required
def result_page(request, key):
    session = get_object_or_404(SessionAnswerUser, session_key=key)
    answered_questions = AnswerUser.objects.filter(session=session)

    # I hope you already know how to use the django queryset.
    # eg:
    # >>> session.user
    # <User: john smith>
    # >>> 
    # >>> answered_questions
    # <QuerySet: [<AnswerUser: foobar lorem>, <AnswerUser: xxxx>]>
    # >>> 
    # >>> answered_questions.first()
    # <AnswerUser: foobar lorem>
    # >>> answered_questions.first().score
    # 3

    ...
    # your context goes here..