每天40分玩转Django：Django表单集

Django表单集

一、知识要点概览表

类别	知识点	掌握程度要求
基础概念	FormSet、ModelFormSet	深入理解
内联表单集	InlineFormSet、BaseInlineFormSet	熟练应用
表单集验证	clean方法、验证规则	熟练应用
自定义配置	extra、max_num、can_delete	理解应用
动态管理	JavaScript动态添加/删除表单	掌握使用

二、基础模型和表单设置

# models.py
from django.db import modelsclass Author(models.Model):name = models.CharField(max_length=100)email = models.EmailField()bio = models.TextField()def __str__(self):return self.nameclass Book(models.Model):author = models.ForeignKey(Author, on_delete=models.CASCADE)title = models.CharField(max_length=200)isbn = models.CharField(max_length=13)publication_date = models.DateField()price = models.DecimalField(max_digits=10, decimal_places=2)def __str__(self):return self.title# forms.py
from django import forms
from .models import Author, Bookclass AuthorForm(forms.ModelForm):class Meta:model = Authorfields = ['name', 'email', 'bio']class BookForm(forms.ModelForm):class Meta:model = Bookfields = ['title', 'isbn', 'publication_date', 'price']

三、基本表单集实现

1. 创建表单集

# forms.py
from django.forms import modelformset_factory, formset_factory# 创建Book模型的表单集
BookFormSet = modelformset_factory(Book,form=BookForm,extra=2,  # 额外空表单数量max_num=5,  # 最大表单数量can_delete=True  # 允许删除
)# 创建自定义表单集
class BaseBookFormSet(forms.BaseModelFormSet):def clean(self):super().clean()titles = []for form in self.forms:if form.cleaned_data:title = form.cleaned_data.get('title')if title in titles:raise forms.ValidationError("书籍标题不能重复")titles.append(title)# 使用自定义表单集基类
BookFormSet = modelformset_factory(Book,form=BookForm,formset=BaseBookFormSet,extra=2
)

2. 视图实现

# views.py
from django.shortcuts import render, redirect
from django.contrib import messages
from .forms import BookFormSet, AuthorFormclass BookFormSetView(View):template_name = 'books/book_formset.html'def get(self, request):formset = BookFormSet(queryset=Book.objects.none())return render(request, self.template_name, {'formset': formset})def post(self, request):formset = BookFormSet(request.POST)if formset.is_valid():instances = formset.save()messages.success(request, f'成功保存{len(instances)}本书籍信息')return redirect('book_list')return render(request, self.template_name, {'formset': formset})def manage_books(request, author_id):author = get_object_or_404(Author, id=author_id)if request.method == 'POST':formset = BookFormSet(request.POST,queryset=Book.objects.filter(author=author))if formset.is_valid():books = formset.save(commit=False)for book in books:book.author = authorbook.save()# 处理删除的书籍for obj in formset.deleted_objects:obj.delete()return redirect('author_detail', pk=author.pk)else:formset = BookFormSet(queryset=Book.objects.filter(author=author))return render(request, 'books/manage_books.html', {'formset': formset,'author': author})

四、内联表单集实现

1. 创建内联表单集

# forms.py
from django.forms import inlineformset_factory# 创建Author-Book内联表单集
BookInlineFormSet = inlineformset_factory(Author,  # 父模型Book,    # 子模型form=BookForm,extra=2,max_num=5,can_delete=True
)# 自定义内联表单集
class BaseBookInlineFormSet(forms.BaseInlineFormSet):def clean(self):super().clean()total_price = 0for form in self.forms:if form.cleaned_data and not form.cleaned_data.get('DELETE', False):price = form.cleaned_data.get('price', 0)total_price += priceif total_price > 1000:raise forms.ValidationError("所有书籍总价不能超过1000")# 使用自定义内联表单集
BookInlineFormSet = inlineformset_factory(Author,Book,form=BookForm,formset=BaseBookInlineFormSet,extra=2
)

2. 视图实现

# views.py
from django.views.generic.edit import UpdateView
from .forms import BookInlineFormSetclass AuthorBooksUpdateView(UpdateView):model = Authorform_class = AuthorFormtemplate_name = 'books/author_books_form.html'def get_context_data(self, **kwargs):context = super().get_context_data(**kwargs)if self.request.POST:context['book_formset'] = BookInlineFormSet(self.request.POST,instance=self.object)else:context['book_formset'] = BookInlineFormSet(instance=self.object)return contextdef form_valid(self, form):context = self.get_context_data()book_formset = context['book_formset']if book_formset.is_valid():self.object = form.save()book_formset.instance = self.objectbook_formset.save()return redirect('author_detail', pk=self.object.pk)return self.render_to_response(self.get_context_data(form=form))

五、表单集模板实现

<!-- templates/books/author_books_form.html -->
{% extends 'base.html' %}
{% load static %}{% block content %}
<div class="container"><h1>编辑作者及其书籍</h1><form method="post">{% csrf_token %}<div class="author-form"><h2>作者信息</h2>{{ form.as_p }}</div><div class="books-formset"><h2>书籍信息</h2>{{ book_formset.management_form }}<div id="book-forms">{% for book_form in book_formset %}<div class="book-form">{{ book_form.non_field_errors }}<div class="form-row"><div class="form-group">{{ book_form.title.label_tag }}{{ book_form.title }}{{ book_form.title.errors }}</div><div class="form-group">{{ book_form.isbn.label_tag }}{{ book_form.isbn }}{{ book_form.isbn.errors }}</div><div class="form-group">{{ book_form.price.label_tag }}{{ book_form.price }}{{ book_form.price.errors }}</div>{% if book_form.instance.pk %}{{ book_form.DELETE }}{% endif %}</div></div>{% endfor %}</div><button type="button" id="add-book" class="btn btn-secondary">添加书籍</button></div><button type="submit" class="btn btn-primary mt-3">保存</button></form>
</div>{% block extra_js %}
<script>
$(document).ready(function() {// 获取表单总数const totalForms = $('#id_book_set-TOTAL_FORMS');// 添加新书籍表单$('#add-book').click(function() {const formCount = parseInt(totalForms.val());const newForm = $('#book-forms .book-form:first').clone(true);// 更新表单索引newForm.find(':input').each(function() {const name = $(this).attr('name').replace('-0-', '-' + formCount + '-');const id = 'id_' + name;$(this).attr({'name': name, 'id': id}).val('');});// 更新标签的for属性newForm.find('label').each(function() {const newFor = $(this).attr('for').replace('-0-', '-' + formCount + '-');$(this).attr('for', newFor);});// 添加新表单到DOM$('#book-forms').append(newForm);totalForms.val(formCount + 1);});
});
</script>
{% endblock %}
{% endblock %}

六、表单集处理流程图

在这里插入图片描述

七、高级用法示例

1. 工厂函数自定义

def get_book_formset(extra=1, max_num=None):return modelformset_factory(Book,form=BookForm,extra=extra,max_num=max_num,validate_max=True,can_delete=True,widgets={'title': forms.TextInput(attrs={'class': 'form-control'}),'isbn': forms.TextInput(attrs={'class': 'form-control'}),'price': forms.NumberInput(attrs={'class': 'form-control'})})# 在视图中使用
def manage_books_dynamic(request):BookFormSet = get_book_formset(extra=2,max_num=10)if request.method == 'POST':formset = BookFormSet(request.POST)if formset.is_valid():formset.save()return redirect('book_list')else:formset = BookFormSet()return render(request, 'books/manage_books.html', {'formset': formset})

2. 条件验证

class BaseBookFormSet(forms.BaseModelFormSet):def clean(self):super().clean()# 检查ISBN唯一性isbns = []for form in self.forms:if form.cleaned_data and not form.cleaned_data.get('DELETE', False):isbn = form.cleaned_data.get('isbn')if isbn in isbns:raise forms.ValidationError('ISBN必须唯一')isbns.append(isbn)# 检查总价格total_price = sum(form.cleaned_data.get('price', 0)for form in self.formsif form.cleaned_data and not form.cleaned_data.get('DELETE', False))if total_price > 1000:raise forms.ValidationError('所有书籍总价不能超过1000')

3. 动态表单处理

# views.py
from django.http import JsonResponseclass DynamicBookFormView(View):def post(self, request):if request.is_ajax():formset = BookFormSet(request.POST)if formset.is_valid():instances = formset.save()return JsonResponse({'status': 'success','message': f'成功保存{len(instances)}本书籍'})else:errors = []for form in formset:for field, error in form.errors.items():errors.append(f"{field}: {error}")return JsonResponse({'status': 'error','errors': errors})return JsonResponse({'status': 'error', 'message': '非法请求'})