Django:如何增加存储在 models.py/Database 中的计数器

Question

我创建了一个小型计数器模型class Counter来存储小型调查应用程序已完成的次数。

我想从views.py中的def did()方法增加models.py中的SurveyWizardOneCounter

谁能告诉我该怎么做？

之前，我在计数器中使用了全局变量，但我发现它无法在网络应用程序中正常工作。我正在尝试学习如何在数据库中创建和存储计数器。任何帮助表示赞赏。

models.py

class Counter(models.Model):                
    SurveyWizardOneCounter = models.SmallIntegerField()
    TotalMaxCounter = models.SmallIntegerField() 

views.py

from survey.models import Counter

def done(self, form_list, **kwargs):

    Counter.SurveyWizardOneCounter += 1  # This is where I am trying to increment the counter

    logger.debug('\n\n SurveyWizardOneCounter = %s', SurveyWizardOneCounter)

    for form in form_list:
        form.save()

    return render(self.request, 'Return_to_AMT.html', {
        'form_data': [form.cleaned_data for form in form_list],            
    })  

Answer 1

由于您有 9 个不同的调查计数器，并且需要在提交调查时递增每个计数器，因此最好定义一个字段 survey_wizard_type ，其可能值为 survey_wizard_one、survey_wizard_two 直到 survey_wizard_nine 以及具有默认值 0 的字段 survey_wizard_count，用于存储该特定的计数调查向导。那么您的数据库中将有 9 条 Counter 模型记录。

models.py

SURVEY_WIZARD_TYPE_CHOICES = ['survey_wizard_one', 'survey_wizard_two', 'survey_wizard_three', 'survey_wizard_four', 'survey_wizard_five', 'survey_wizard_six', 'survey_wizard_seven', 'survey_wizard_eight', 'survey_wizard_nine']

class Counter(models.Model): 

    survey_wizard_type = models.CharField(choices=SURVEY_WIZARD_TYPE_CHOICES)
    survey_wizard_count = models.SmallIntegerField(default=0)
    total_max_counter = models.SmallIntegerField() 

然后在您的 views.py 中，您可以使用 get_or_create 方法来查找具有给定 survey_wizard_type< 的 Counter 对象，如有必要，创建一个。然后将 survey_wizard_count 加 1 并将该对象保存到数据库中。

views.py

from django.db.models import F
from survey.models import Counter

def done(self, form_list, **kwargs):

    survey_counter = Counter.objects.get_or_create(survey_wizard_type= 'survey_wizard_x') # x can be any value from one to nine
    survey_counter.survey_wizard_count = F('survey_wizard_count') + 1 
    survey_counter.save()

    logger.debug('\n\n SurveyWizardOneCounter = %s', SurveyWizardOneCounter)

    for form in form_list:
        form.save()

    return render(self.request, 'Return_to_AMT.html', {
        'form_data': [form.cleaned_data for form in form_list],            
    })   

编辑

Rahul 提供了解决方案，但这是我最终使用的代码

models.py

class Counter(models.Model):

    SURVEY_WIZARD_TYPE_CHOICES = (
                              ('SURVEY_WIZARD_ONE', 'survey_wizard_one'),
                              ('SURVEY_WIZARD_TWO', 'survey_wizard_two'), 
                              ('SURVEY_WIZARD_THREE', 'survey_wizard_three'), 
                              ('SURVEY_WIZARD_FOUR', 'survey_wizard_four'), 
                              ('SURVEY_WIZARD_FIVE', 'survey_wizard_five'),
                              ('SURVEY_WIZARD_SIX', 'survey_wizard_six'), 
                              ('SURVEY_WIZARD_SEVEN', 'survey_wizard_seven'),
                              ('SURVEY_WIZARD_EIGHT', 'survey_wizard_eight'),
                              ('SURVEY_WIZARD_NINE', 'survey_wizard_nine'),
                              )   

    survey_wizard_type = models.CharField(max_length=1000, choices=SURVEY_WIZARD_TYPE_CHOICES)
    survey_wizard_count = models.SmallIntegerField(default=0)
    total_max_counter = models.SmallIntegerField(default=0) 

views.py

def done(self, form_list, **kwargs):

    survey_counter = Counter.objects.get_or_create(survey_wizard_type= 'survey_wizard_one')[0] # x can be any value from one to nine
    survey_counter.survey_wizard_count = F('survey_wizard_count') + 1 
    survey_counter.save()

    for form in form_list:
        form.save()

    return render(self.request, 'Return_to_AMT.html', {
        'form_data': [form.cleaned_data for form in form_list],            
    })