擅长:python、mysql、java
<p>如果您一直使用django<;1.7,那么可以使用<code>self._errors.add</code>(感谢@Sayse)。如果您使用的是django 1.7或更新版本,则可以使用<a href="https://docs.djangoproject.com/en/1.8/ref/forms/api/#django.forms.Form.add_error" rel="nofollow">^{<cd2>}</a>:</p>
<blockquote>
<p>This method allows adding errors to specific fields from within the
Form.clean() method, or from outside the form altogether; for instance
from a view.</p>
<p>The field argument is the name of the field to which the errors should
be added. If its value is None the error will be treated as a
non-field error as returned by Form.non_field_errors().</p>
<p>The error argument can be a simple string, or preferably an instance
of ValidationError. See Raising ValidationError for best practices
when defining form errors.</p>
</blockquote>
<p>您应该在<code>form</code>的<code>clean</code>方法中或在视图中调用<code>form.is_valid()</code>之前,检查数据库中是否没有相应的记录,并将错误附加到字段:</p>
<pre><code>form.addError("region", ValidationError('No corresponding data exists'))
</code></pre>
<p><em>PS:要打开“黄色异常页”,请关闭设置中的<code>DEBUG</code>。</em></p>