Django：更新/编辑填充表单和表单集

Question

谁能帮我回答为什么我的更新视图功能不运行？它返回填充的表单和表单集，没有错误消息（并且没有文件附件）。

这发生在使用 formset（使用 modelformset_factory 制作）更新函数后：

def recipe_update(request, id=None):
if request.method == 'GET':
    instance = get_object_or_404(Recipe, id=id, user=request.user)
    form = RecipeForm(request.POST or None, request.FILES or None, instance=instance)
    formset = IngredientModelFormset(queryset=Ingredient.objects.filter(recipe=instance))
elif request.method == 'POST':
    instance = get_object_or_404(Recipe, id=id, user=request.user)
    form = RecipeForm(request.POST, request.FILES or None)
    formset = IngredientModelFormset(request.POST, request.FILES or None)
    if form.is_valid() and formset.is_valid():
        recipe = form.save()
        for forms in formset:
            ingredient = forms.save(commit=False)
            ingredient.recipe = recipe
            ingredient.save()
        return redirect(recipe.get_absolute_url())
context = {
    "instance": instance,
    "form": form,
    'formset': formset,
}
return render(request, "recipes/recipe_form.html", context)

create 函数工作正常：

def recipe_create(request):
if request.method == 'GET':
    form = RecipeForm(request.POST or None, request.FILES or None)
    formset = IngredientModelFormset(queryset=Ingredient.objects.none())
elif request.method == 'POST':
    form = RecipeForm(request.POST, request.FILES or None)
    formset = IngredientModelFormset(request.POST, request.FILES or None)
    if form.is_valid() and formset.is_valid():
        recipe = form.save()
        for forms in formset:
            ingredient = forms.save(commit=False)
            ingredient.recipe = recipe
            ingredient.save()
        return redirect(recipe.get_absolute_url())
context = {
    "form": form,
    'formset': formset,
}
return render(request, "recipes/recipe_form.html", context)

非常感谢！

更新

我根据建议更改了代码，现在出现以下错误：['ManagementForm data is missing or has been tampered with']

我在模板中使用 management_form：

{{ formset.management_form }}
{% for forms in formset %}
<div class="row form-row spacer">
    <div class="col-2">
        <label>{{ forms.name.label }}</label>
    </div>
    <div class="col-4">
        <div class="input-group">
            {{ forms.name }}
            <div class="input-group-append">
                <button class="btn btn-success add-form-row">+</button>
            </div>
        </div>
    </div>
</div>
{% endfor %}

这是更新后的视图代码：

def recipe_update(request, id=None):
  instance = get_object_or_404(Recipe, id=id, user=request.user)
  form = RecipeForm(request.POST, request.FILES or None, instance=instance)
  formset = IngredientModelFormset(request.POST, request.FILES or None, instance=instance)
  if form.is_valid() and formset.is_valid():
    recipe = form.save()
    recipe.user = request.user
    recipe.save()
    for forms in formset:
        ingredient = forms.save(commit=False)
        ingredient.recipe = recipe
        ingredient.save()
    return redirect(recipe.get_absolute_url())
  context = {
    "instance": instance,
    "form": form,
    'formset': formset,
  }
  return render(request, "recipes/recipe_form.html", context)

Answer 1

您需要使用inline formset。在更新视图中，您还需要为发布请求传递实例参数：

def recipe_update(request, id=None):
    if request.method == 'GET':
        instance = get_object_or_404(Recipe, id=id, user=request.user)   
        form = RecipeForm(request.POST or None, request.FILES or None, instance=instance)
        formset = IngredientModelFormset(queryset=Ingredient.objects.none(), instance=instance)
    elif request.method == 'POST':
        instance = get_object_or_404(Recipe, id=id, user=request.user)
        form = RecipeForm(request.POST, request.FILES or None, instance=instance)
        formset = IngredientModelFormset(request.POST, request.FILES or None, instance=instance)

您也不需要使用request.POST or None 快捷方式检查请求类型。您可以简单地将代码重写为：

def recipe_update(request, id=None):
    instance = get_object_or_404(Recipe, id=id, user=request.user)  
    form = RecipeForm(request.POST or None, request.FILES or None, instance=instance)
    formset = IngredientModelFormset(request.POST or None, request.FILES or None, instance=instance)
    if form.is_valid() and formset.is_valid():
    # rest of your code