modelformset_factory 不将实例保存到数据库

Question

我试图在我的页面上创建一个带有实例的表单集，但表单集根本不保存实例。额外的字段保存效果很好，但我无法理解实例有什么问题。我在页面上有很多表格，这是最后一个，没有保存：我的看法：

def details(request, username, slug):
    sm = Social_media.objects.all()
    profile = get_object_or_404(Profiles, user__username=username)
    site = get_object_or_404(MySites, slug=slug, user__username=username)
    ftp = get_object_or_404(FTP, site=site)
    FtpPathFormSet = forms.modelformset_factory(FtpPath,form=FtpPathForm,extra=1)
    sjim_ops = SjimOperations.objects.filter(user=request.user).order_by('-date')
    sjim_det = SjimDetails.objects.all()

    if request.method == 'POST':

    // other forms and logic 

       if 'change3' in request.POST:
            newsite = NewSiteForm(instance=site)
            newftp = NewFtpForm(instance=ftp)
            ftppath = FtpPathFormSet(request.POST)
            if ftppath.is_valid:
                print('here')
                i = 0
                instances = ftppath.save(commit=False)
                for instance in instances:
                    print('here2')
                    instance.ftp = ftp
                    instance.recursive = request.POST.get('form-'+str(i)+'-recursive')

                    if instance.recursive == 'on':
                        instance.recursive = True
                    else:
                        instance.recursive = False

                    instance.period = request.POST.get('form-'+str(i)+'-period')
                    try:
                        testconnect = ftplibr(ftp.host)
                        testconnect.login(user=ftp.ftpuser, passwd=ftp.password)
                        testconnect.cwd(instance.path)
                        instance.find = True
                        testconnect.quit()
                    except:
                        instance.find = False

                    ftppath.save()
                    i =+ 1
                return redirect('main:details', username=username, slug=site.slug)

型号：

class FtpPath(models.Model):
    period = (
        ('Раз в сутки','Раз в сутки'),
        ('Раз в неделю','Раз в неделю'),
        ('Раз в 2 недели','Раз в 2 недели')
        )

    ftp = models.ForeignKey(FTP, on_delete=models.CASCADE)
    path = models.CharField(max_length=200, blank=True)
    period = models.CharField(choices=period, max_length=20, null=True, blank=True)
    find = models.BooleanField(null=True, default=False)
    recursive = models.BooleanField(null=True, default=False)

    class Meta:
        verbose_name = 'FTP path'
        verbose_name_plural = 'FTP paths'

表格：

class FtpPathForm(forms.ModelForm):
    path = forms.CharField(widget=forms.TextInput(attrs={'type':'text','class':'effect-16'}), required=False)
    recursive = forms.BooleanField(widget=forms.CheckboxInput(attrs={}), required=False)
    period = forms.CharField(widget=forms.TextInput(attrs={'type':'text','style':'display:none','class':'period-input'}), required=False, label='')

    class Meta:
        model = FtpPath
        fields = ('path', 'recursive','period', 'find')

模板：

<form method="POST" id="path-form">
       {% csrf_token %}
       {{ ftppath.management_form }}
       <div class="info_tab_3col">
        <div class="form_title">Выбрать папки</div>
        <div class="form_folders">
        {% for ftppath in ftppath %}
        {% if ftppath.find.value == True %}
         <div class="form_folder">
         {% else %}
        <div class="form_folder form_folder_error">
        {% endif %}
        <div class="ftp_form_item">
        <div class="ftp_f_long ftp_f_long_i">
        <div class="input-effect">
        {{ ftppath.path }}
        <label>Путь на сервере</label>
        <span class="focus-border"></span>
        </div>
        </div>
        <div class="ftp_form_s ftp_form_s_i">
        <div class="checkbox_box">
        {{ ftppath.recursive }}
        <label for="id_form-{{ forloop.counter0 }}-recursive">
        <span><!-- This span is needed to create the "checkbox" element --></span>
        Рекурсивно
        </label>
        </div>
        </div>
        </div>
        <div class="ftp_form_item ftp_form_item_type">
        <div class="select_wrapper">
        {{ ftppath.period }}
        <div class="select_wrapper_val"></div>
        <span class="select_wrapper_label">Период</span>
        <span class="input_error error-ftppath"></span>
        <div class="select_list">
        <div class="select_list_item">Раз в сутки</div>
        <div class="select_list_item">Раз в неделю</div>
        <div class="select_list_item">Раз в 2 недели</div>
        </div>
        </div>
        </div>
           </div>
       {% endfor %}
       </div>
        <div class="form_button form_button_ftp">
               <button class="btn" type="submit" name="change3">
                   <span>Изменить</span>
                </button>
         </div>
      </div>
         </form>

所以 formset 在页面上呈现正常：我 1 instance and one extra field. 如果我单击提交字段，该字段已经在数据库和页面上没有更改实例。如果我将我的视图 is_valid: 更改为 is_valid():，看起来表单保存在页面上，而不是数据库中，所以如果我转到其他页面并返回，则不会保存任何内容。如果我删除我认为的所有逻辑，它的工作方式相同，我不知道我做错了什么，请帮忙！

Answer 1

问题是您应该在循环结束时调用 instance.save() 而不是 ftppath.save()。

另外注意is_valid是方法，需要调用：if ftppath.is_valid():

另请注意，保持这样的计数器并手动递增它是非常不符合 Python 风格的。相反，使用 enumerate.

但实际上，您无论如何都不想使用其中任何一个；不要通过连接表单 ID 从 POST 获取数据，您应该从表单 cleaned_data 本身获取数据。如果这样做，则无需手动将其与 "on" 进行比较；这就是表单清理过程 已经为您完成的工作 。

所以你应该遍历表单，然后保存每一个：

if ftppath.is_valid():
    for form in ftppath.forms:
        instance = form.save(commit=False)
        instance.ftp = ftp
        instance.recursive = form.cleaned_data['recursive']
        instance.period = form.cleaned_data['period']
        try:
           ...
        except ftplib.all_errors:   # always use a specific error
           ...
        instance.save()

最后，您确定需要手动设置这两个值吗？它们是模型上的字段并在表单的字段属性中指定，因此 Django 应该已经为您设置了它们。

modelformset_factory 不将实例保存到数据库

modelformset_factory doesnt save instances to database

django

python-3.x

django-forms

django-views

formset