Question

我正在或多或少地测试Django Doc中的“写作验证器”。所以我写了我自己的验证器，它似乎可以工作。

例如：当我创建一个重量更高的新动物时，我的表格没有保存，则为100。这就是我要测试的。

但是我不知道如何在模板中显示错误消息。

models.py

<...>

class Animal(models.Model):
    name = models.CharField(max_length=40)
    weight = models.DecimalField(max_digits=5, decimal_places=2)
    species = models.ForeignKey('Species', on_delete=models.CASCADE)
    farmer = models.ForeignKey('Farmer', related_name='farmername', on_delete=models.CASCADE)

    objects = AnimalManager() # --- link to Manager

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse("datainput:animal_detail", kwargs={"id": self.id})

forms.py

<...>

from .validator import validate_gtr

<...>

class AnimalForm(forms.ModelForm):
    weight = forms.DecimalField(validators=[validate_gtr])

    class Meta:
        model = Animal
        fields = [
            'name',
            'weight',
            'species',
            'farmer',    
        ]

validator.py

from django.core.exceptions import ValidationError
from django.utils.translation import gettext_lazy as _



def validate_gtr(value):
    if value > 100:
        raise ValidationError(
            _('(value) Kg. Animal is too heavy'),
            params={'value': value},
        )

views.py

 class AnimalCreateView(CreateView):
        template_name ="datainput/create_animal.html"
        form_class = AnimalForm
        queryset = Animal.objects.all()

create_animal.html

{% extends 'base.html' %}

{% load static %}

{% block custom_css %}
<link rel="stylesheet" type="text/css" href="{% static 'css/home_styles.css' %}">
{% endblock %}


    {% block content %}

<div class="container-fluid">

    <!-- Row -->
    <div class="row">
        <div class="col-6 offset-md-3">

                <h1>Please insert a new animal</h1>

                {% load widget_tweaks %}

                <form method="post">
                    {% csrf_token %}

                    {% for hidden in form.hidden_fields %}
                    {{ hidden }}
                    {% endfor %}

                    <div class="form-group">
                        <label for="{{ form.name.label }}"> {{ form.name.label }} </label>
                        {% render_field form.name placeholder=form.name.help_text class+="form-control" %}
                    </div>
                    <div class="form-group">
                        <label for="{{ form.weight.label }}"> {{ form.weight.label }} </label>
                        {% render_field form.weight placeholder=form.weight.help_text class+="form-control" %}
                    </div>
                    <div class="form-group">
                        <label for="{{ form.species.label }}"> {{ form.species.label }} </label>
                        {% render_field form.species placeholder=form.species.help_text class+="form-control" %}
                    </div>
                    <div class="form-group">
                        <label for="{{ form.farmer.label }}"> {{ form.farmer.label }} </label>
                        {% render_field form.farmer placeholder=form.farmer.help_text class+="form-control" %}
                    </div>
                    <div class="form-group">
                        <button type="submit" class="btn btn-success">
                            <span class="glyphicon glyphicon-ok"></span> Save
                        </button>
                        <a href="{% url 'home' %}" class="btn btn-default">Cancel</a>
                    </div>
                </form>

        </div>
    </div>
        <!-- Row End --> 
</div>
<!-- Container End -->



{% endblock %}

所以我想我的模板中需要一个错误字段，而视图中可能需要一些错误上下文？

Answer 1

就像@dirkgroten一样，它所需要的只是模板中的错误字段引用。就我而言，我只是在表单中引用了它。

create_animal.html

<...>
  {{form.errors}}
<...>

用Django编写验证器：如何显示验证错误消息？

1 个答案: