Django:正确显示formset错误

Question

我有一个模型的内联formset,它有一个unique_together约束.因此,当我输入不满足此约束的数据时,它会显示:

__all__Please correct the duplicate values below.

代码,这是:

    {% for error in formset.errors %}
        {{ error }}<br/>
    {% endfor %}

我不太喜欢__all__错误的开头,它很明显是字典键,所以我试过:

    {% for key, error in formset.errors %}
        {{ key }}: {{ error }}<br/>
    {% endfor %}

但是我得到的只是:

__all__:

{{error}}根本不会显示.那么这里发生了什么？如何正确显示错误？

Answer 1

我认为这里的问题是formset.errors字典列表,而不是单个字典.

从formset上的Django文档页面:

>>> formset.errors
[{}, {'pub_date': [u'This field is required.']}]

看看这样的东西是否解决了问题:( 根据askers评论更新)

{% for dict in formset.errors %}
    {% for error in dict.values %}
        {{ error }}
    {% endfor %}
{% endfor %}

如果失败了,我会尝试使用manage.py shell,并尝试在python shell中重现你的情况......这样就可以很容易地检查各种值并找出你需要做什么.

Answer 2

for循环是不必要的,应该使用以下内容正确显示这些错误:

{{ formset.non_form_errors }}

Answer 3

Here is a clarification for anyone encountering similar issues of errors not being rendered in template:

If you have and error regarding the formset as a whole, use:

{{ formset.non_form_errors }}

this basically returns errors in __all__ entry from formset.errors. It is documented as:

    """
    Returns an ErrorList of errors that aren't associated with a particular
    form -- i.e., from formset.clean(). Returns an empty ErrorList if there
    are none.
    """

However if you are rendering forms from formset and some errors are not being renderd, you are probably missing:

{% for form in formset.forms %}
    {# ... #}
    {{ form.non_field_errors }}
{% endfor %}

this returns errors in __all__ entry from form.errors. Those are, analogous to the non_form_errors, the errors that aren't associated with a particular field, but rather with the field relations. For example if you had a form with fields From and To, and you validate if From value is smaller then To value, the tag {{ form.non_field_errors }} could render the following error:

'The From value must be smaller than the To value'