{"title":"クラスベースのビューでフォームを扱う","version":"2.2","locale":"ja","docname":"topics/class-based-views/generic-editing","url":"/ja/2.2/topics/class-based-views/generic-editing/","canonical":"https://djangodocs.dev/ja/2.2/topics/class-based-views/generic-editing/","summary":"フォームの処理には、一般に3つの場合分けが存在します。 最初の GET リクエスト (空白またはデフォルト値が埋め込まれたフォームを返す) 無効なデータの POST リクエスト (よくあるパターンは、エラー表示を追加したフォームを再表示する) 有効なデータの POST リクエスト (データを処理し、普通はリダイレクトを行う)…","html":"

クラスベースのビューでフォームを扱うLink to this heading#

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フォームの処理には、一般に3つの場合分けが存在します。

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これらの処理を自分で実装しようとすると、多くの場合、多数の繰り返しの定型コードを書くことになってしまいます (Using a form in a view を参照)。これを避けるために、Django はフォームを処理するための一般的なクラスビューを用意しています。

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基本的なフォームLink to this heading#

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以下のような単純なコンタクトフォームがあったとします。

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forms.py
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Python
from django import forms\n\nclass ContactForm(forms.Form):\n    name = forms.CharField()\n    message = forms.CharField(widget=forms.Textarea)\n\n    def send_email(self):\n        # send email using the self.cleaned_data dictionary\n        pass\n
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このとき、ビューは FormView を使用することで構築することができます。

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views.py
\n
Python
from myapp.forms import ContactForm\nfrom django.views.generic.edit import FormView\n\nclass ContactView(FormView):\n    template_name = 'contact.html'\n    form_class = ContactForm\n    success_url = '/thanks/'\n\n    def form_valid(self, form):\n        # This method is called when valid form data has been POSTed.\n        # It should return an HttpResponse.\n        form.send_email()\n        return super().form_valid(form)\n
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メモ:

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モデルフォームLink to this heading#

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ジェネリックビューが輝きを見せるのは、モデルとともに使用した時です。ジェネリックビューは ModelForm を自動的に生成するので、どのモデルクラスを使うのかを選択することができます。

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Model form views provide a\nform_valid() implementation\nthat saves the model automatically. You can override this if you have any\nspecial requirements; see below for examples.

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You don't even need to provide a success_url for\nCreateView or\nUpdateView - they will use\nget_absolute_url() on the model object if available.

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カスタムした ModelForm を使用したい場合 (例えば、追加的なバリデーションを加えたい場合)、シンプルに form_class をビューでセットしてください。

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最初に、Author クラスに get_absolute_url() を追加する必要があります:

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models.py
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Python
from django.db import models\nfrom django.urls import reverse\n\nclass Author(models.Model):\n    name = models.CharField(max_length=200)\n\n    def get_absolute_url(self):\n        return reverse('author-detail', kwargs={'pk': self.pk})\n
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そうしたら、CreateView およびその仲間たちを使って実際に動作させることができます。ここでは一般的なクラスベースのビューのみを設定している点が重要です; 自分自身でロジックを書く必要はありません:

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views.py
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Python
from django.urls import reverse_lazy\nfrom django.views.generic.edit import CreateView, DeleteView, UpdateView\nfrom myapp.models import Author\n\nclass AuthorCreate(CreateView):\n    model = Author\n    fields = ['name']\n\nclass AuthorUpdate(UpdateView):\n    model = Author\n    fields = ['name']\n\nclass AuthorDelete(DeleteView):\n    model = Author\n    success_url = reverse_lazy('author-list')\n
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The fields attribute works the same way as the fields attribute on the\ninner Meta class on ModelForm. Unless you define the\nform class in another way, the attribute is required and the view will raise\nan ImproperlyConfigured exception if it's not.

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If you specify both the fields\nand form_class attributes, an\nImproperlyConfigured exception will be raised.

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Finally, we hook these new views into the URLconf:

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urls.py
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Python
from django.urls import path\nfrom myapp.views import AuthorCreate, AuthorDelete, AuthorUpdate\n\nurlpatterns = [\n    # ...\n    path('author/add/', AuthorCreate.as_view(), name='author-add'),\n    path('author/<int:pk>/', AuthorUpdate.as_view(), name='author-update'),\n    path('author/<int:pk>/delete/', AuthorDelete.as_view(), name='author-delete'),\n]\n
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Models and request.userLink to this heading#

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To track the user that created an object using a CreateView,\nyou can use a custom ModelForm to do this. First, add\nthe foreign key relation to the model:

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models.py
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Python
from django.contrib.auth.models import User\nfrom django.db import models\n\nclass Author(models.Model):\n    name = models.CharField(max_length=200)\n    created_by = models.ForeignKey(User, on_delete=models.CASCADE)\n\n    # ...\n
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In the view, ensure that you don't include created_by in the list of fields\nto edit, and override\nform_valid() to add the user:

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views.py
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Python
from django.contrib.auth.mixins import LoginRequiredMixin\nfrom django.views.generic.edit import CreateView\nfrom myapp.models import Author\n\nclass AuthorCreate(LoginRequiredMixin, CreateView):\n    model = Author\n    fields = ['name']\n\n    def form_valid(self, form):\n        form.instance.created_by = self.request.user\n        return super().form_valid(form)\n
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LoginRequiredMixin prevents users who\naren't logged in from accessing the form. If you omit that, you'll need to\nhandle unauthorized users in form_valid().

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AJAX の例Link to this heading#

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以下に挙げるのは、「普通の」フォームが POST するのと同様に AJAX リクエストで動作するフォームの簡単な実装例です。

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Code
from django.http import JsonResponse\nfrom django.views.generic.edit import CreateView\nfrom myapp.models import Author\n\nclass AjaxableResponseMixin:\n    """\n    Mixin to add AJAX support to a form.\n    Must be used with an object-based FormView (e.g. CreateView)\n    """\n    def form_invalid(self, form):\n        response = super().form_invalid(form)\n        if self.request.is_ajax():\n            return JsonResponse(form.errors, status=400)\n        else:\n            return response\n\n    def form_valid(self, form):\n        # We make sure to call the parent's form_valid() method because\n        # it might do some processing (in the case of CreateView, it will\n        # call form.save() for example).\n        response = super().form_valid(form)\n        if self.request.is_ajax():\n            data = {\n                'pk': self.object.pk,\n            }\n            return JsonResponse(data)\n        else:\n            return response\n\nclass AuthorCreate(AjaxableResponseMixin, CreateView):\n    model = Author\n    fields = ['name']\n
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","rootId":"form-handling-with-class-based-views","toc":[{"title":"基本的なフォーム","anchor":"basic-forms","children":[]},{"title":"モデルフォーム","anchor":"model-forms","children":[]},{"title":"Models and request.user","anchor":"models-and-request-user","children":[]},{"title":"AJAX の例","anchor":"ajax-example","children":[]}],"breadcrumbs":[{"docname":"topics/index","title":"Django を使う","url":"/ja/2.2/topics/"},{"docname":"topics/class-based-views/index","title":"クラスベースビュー","url":"/ja/2.2/topics/class-based-views/"}],"prev":{"docname":"topics/class-based-views/generic-display","title":"ビルトインのクラスベースのジェネリックビュー","url":"/ja/2.2/topics/class-based-views/generic-display/"},"next":{"docname":"topics/class-based-views/mixins","title":"クラスベースのビューでミックスインを使用する","url":"/ja/2.2/topics/class-based-views/mixins/"},"formats":{"html":"/ja/2.2/topics/class-based-views/generic-editing/","markdown":"/ja/2.2/topics/class-based-views/generic-editing.md","json":"/ja/2.2/topics/class-based-views/generic-editing.json"},"source":"https://github.com/django/django/blob/stable/2.2.x/docs/topics/class-based-views/generic-editing.txt","official":"https://docs.djangoproject.com/ja/2.2/topics/class-based-views/generic-editing/","inVersions":["6.1","6.0","5.2","5.1","5.0","4.2","4.1","4.0","3.2","3.1","3.0","2.2","2.1","2.0","1.11","1.10","1.9"],"inLocales":["en","zh-hans","fr","ja","id","pt-br","ko","es","el","pl"]}