Django的：改變MinLengthValidator錯誤消息

Question

這裏是如何MinLengthValidator在Django的定義：

class MinLengthValidator(BaseValidator): 
    compare = lambda self, a, b: a < b 
    clean = lambda self, x: len(x) 
    message = ungettext_lazy(
     'Ensure this value has at least %(limit_value)d character (it has %(show_value)d).', 
     'Ensure this value has at least %(limit_value)d characters (it has %(show_value)d).', 
     'limit_value') 
    code = 'min_length' 

我試着在我的代碼更改錯誤信息是這樣的：

password_min_length_validator = MinLengthValidator(8) 
password_min_length_validator.message = ungettext_lazy(
    'Ensure password has at least %(limit_value)d character (it has %(show_value)d).', 
    'Ensure password has at least %(limit_value)d characters (it has %(show_value)d).', 
    'limit_value') 

但我得到這個錯誤：

ugettext() takes exactly 1 argument (3 given) 

我這樣做就像django.core.validators那樣做。

Answer 1

看起來您使用的是早期版本的Django，因此您應該將代碼基於您的Django版本的MinLengthValidator，而不是當前的實現。由於在Django 1.6中更改了ungettext_lazy方法，因此您會收到錯誤消息（請參見憑證#19160）。

例如，在Django 1.5.X，你會怎麼做：

from django.utils.translation import ugettext_lazy as _ 

class MinLengthValidator(BaseValidator): 
    compare = lambda self, a, b: a < b 
    clean = lambda self, x: len(x) 
    message = _('Ensure this value has at least %(limit_value)d characters (it has %(show_value)d).') 
    code = 'min_length' 

password_min_length_validator = MinLengthValidator(8) 
password_min_length_validator.message = _(
    'Ensure password has at least %(limit_value)d characters (it has %(show_value)d).', 
) 

而不是設置消息你實例驗證後屬性的，你可以繼承它：

class MyMinLengthValidator(MinLengthValidator): 
    message = _('Ensure my_field has at least %(limit_value)d characters (it has %(show_value)d).') 

my_min_length_validator = MyMinLengthValidator(8) 

另外，您可以在表單字段上使用error_messages選項：

class MyForm(forms.Form): 
    my_field = forms.CharField(validators=[MinLengthValidator(8)], 
         error_messages={'min_length': _('Ensure my_field has at least %(limit_value)d characters (it has %(show_value)d).') 
})