Django ModelForm-防止在视图中保存

如果我能正确理解你的问题,这就行了,

from django.http import HttpResponse


def my_form_view(request):
    if request.method == "POST":
        form = PurchaseForm(request.POST)
        if form.is_valid():
            purchase = form.save(commit=False)
            purchase.contract = Contract.objects.get(number=slug)
            weight = form.cleaned_data.get('weight')
            if check_weight(weight, purchase.contract):
                weight_type = purchase.contract.supplier.market.weights
                purchase.lbs, purchase.kgs = generate_weights(weight, weight_type)
                purchase.save()
                return HttpResponse("save success")
            return HttpResponse("'check_weight' returned False")
    else:  # if a GET (or any other method) we'll create a blank form
        form = PurchaseForm()
    return render(request, 'some_html_template.html', {'form': form})