同一模板中的模型表单集和常规模型表单？答案

【问题标题】：Model Formset and regular ModelForm in same template?同一模板中的模型表单集和常规模型表单？
【发布时间】：2021-02-20 14:56:57
【问题描述】：

我有两个模型：

Project:

class Project(Model):
    
    name = CharField(max_length=50)
    members = ManyToManyField("accounts.User", through='ProjectUser')
    organization = ForeignKey(Organization, related_name="projects", on_delete=CASCADE)

    def __str__(self):
        return self.name

和Task:

class Task(Model):
    task = CharField(max_length=100)
    project = ForeignKey(Project, on_delete=CASCADE)

    class Meta:
        db_table = 'task'

我有一个UpdateView 类：

class ProjectUpdateView(UpdateView):
    form_class = ProjectUpdateForm
    template_name = 'projects/project_edit.html'
    success_url = reverse_lazy('projects:list')

如何允许用户在编辑Project 实例的同一页面上添加任务（通过内联表单集）？

例如，用户可以在一个地方编辑Project name 和添加/删除Task 实例的一种合并表单

【问题讨论】：

标签： django django-models django-forms inline-formset

【解决方案1】：

表单/表单集：

首先，为您的任务模型创建一个表单和一个表单集

class TaskForm(ModelForm):
    class Meta:
        model = Task
        fields = ['task']

    def __init__(self, *args, **kwargs):
        super(TaskForm, self).__init__(*args, **kwargs)



class TaskBaseFormSet(BaseInlineFormSet):
    def __init__(self, *args, **kwargs):
        super(TaskBaseFormSet, self).__init__(*args, **kwargs)



TaskFormset = inlineformset_factory(
    Project,  # parent_model
    Task,  # model
    form=TaskForm, 
    formset=TaskBaseFormSet
)

或者，如果您不需要 TaskForm 类，创建 TaskFormset 所需要做的就是这个

TaskFormset = inlineformset_factory(Project, Task, fields=('task',))

查看：

我看到您正在为您的视图使用 UpdateView 类，因此您可以这样做以在您的 context_data 中获取一个 TaskFormset，因此现在您可以在您的“template_name”属性中声明的模板中使用 TaskFormset更新视图类

def get_context_data(self, **kwargs):
    context = super().get_context_data(**kwargs)

    if self.request.POST:
        context['task_formset'] = forms.TaskFormset(self.request.POST)
    else:
        context['task_formset'] = forms.TaskFormset()


    return context

# In the form_valid method of your UpdateView class you can validate the data 
# and assign the Project instance to all the tasks that were create by the formsets

def form_valid(self, form):

     task_formset = context['task_formset']

     # you can validate formset data like this
     if not task_formset.is_valid():
        return self.form_invalid(form)


     project = form.save()
     # Here you assign the Project instance to the Tasks
     task_formset.instance = project
     task_formset.save()

     return super().form_valid(form)

模板：

现在您需要做的就是使用循环打印 management_form 和表单集中的每个表单，如下面的代码所示

<form method="post">

    <!-- Your ProjectUpdateForm form here... -->

    {{ task_formset.management_form }}
    <table>
        {% for form in task_formset %}
        {{ form }}
        {% endfor %}
    </table>
</form>

希望这能有所帮助！有一些指向官方 Django 文档的链接可能对您有用：

https://docs.djangoproject.com/en/3.1/topics/forms/formsets/#using-a-formset-in-views-and-templates

https://docs.djangoproject.com/en/3.1/topics/forms/modelforms/#inline-formsets

https://docs.djangoproject.com/en/3.1/ref/forms/models/#inlineformset-factory

【讨论】：