ModelForm
Generate a form straight from a model with ModelForm.
Syntax
class PostForm(forms.ModelForm): class Meta: model = PostWhen a form maps directly to a model, use a ModelForm. It builds the fields from the model and can save the data with a single form.save() call.
Declare the model and fields in an inner Meta class.
Example
# blog/forms.py
from django import forms
from .models import Post
class PostForm(forms.ModelForm):
class Meta:
model = Post
fields = ["title", "body", "published"]
# In a view:
# form = PostForm(request.POST)
# if form.is_valid():
# form.save() # creates the PostWhen to use it
- A developer uses ModelForm for a Post create page so the form fields are automatically derived from the model.
- A team uses ModelForm.save() to insert a new database record directly from form data without writing SQL.
- A developer uses the 'fields' Meta option to expose only a subset of model fields in the public-facing form.
More examples
Define a ModelForm
Creates a form that maps directly to the Post model, exposing only the specified fields.
from django import forms
from .models import Post
class PostForm(forms.ModelForm):
class Meta:
model = Post
fields = ["title", "body", "tags"]Save a new record from form
Uses commit=False to set the author before saving, then calls save() to persist the record.
def post_create(request):
if request.method == "POST":
form = PostForm(request.POST)
if form.is_valid():
post = form.save(commit=False)
post.author = request.user
post.save()
return redirect(post)
else:
form = PostForm()
return render(request, "blog/post_form.html", {"form": form})Edit an existing record
Passes instance=post to pre-populate the form with existing data for editing.
def post_edit(request, pk):
post = get_object_or_404(Post, pk=pk, author=request.user)
form = PostForm(request.POST or None, instance=post)
if form.is_valid():
form.save()
return redirect(post)
return render(request, "blog/post_form.html", {"form": form})
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