Django高階程式設計之自定義Field實現多語言
阿新 • • 發佈:2019-07-02
自定義資料庫欄位
擴充套件預設的models.CharField和models.TextField使之成為支援多語言的欄位。
可以輕鬆實現複用,無需配置多餘選項
from django.conf import settings from django.db import models from django.utils.translation import get_language class MultilingualField(models.Field): SUPPORTED_FIELD_TYPES = [models.CharField, models.TextField] def __init__(self, verbose_name=None, **kwargs): self.localized_field_model = None for model in MultilingualField.SUPPORTED_FIELD_TYPES: if issubclass(self.__class__, model): self.localized_field_model = model self._blank = kwargs.get("blank", False) self._editable = kwargs.get("editable", True) super().__init__(verbose_name, **kwargs) @staticmethod def localized_field_name(name, lang_code): lang_code_safe = lang_code.replace("-", "_") return f"{name}_{lang_code_safe}" def get_localized_field(self, lang_code, lang_name): _blank = (self._blank if lang_code == settings.LANGUAGE_CODE else True) localized_field = self.localized_field_model( f"{self.verbose_name} ({lang_name})", name=self.name, primary_key=self.primary_key, max_length=self.max_length, unique=self.unique, blank=_blank, null=False, # we ignore the null argument! db_index=self.db_index, default=self.default or "", editable=self._editable, serialize=self.serialize, choices=self.choices, help_text=self.help_text, db_column=None, db_tablespace=self.db_tablespace) return localized_field def contribute_to_class(self, cls, name, private_only=False): def translated_value(self): language = get_language() val = self.__dict__.get( MultilingualField.localized_field_name( name, language)) if not val: val = self.__dict__.get( MultilingualField.localized_field_name( name, settings.LANGUAGE_CODE)) return val # generate language-specific fields dynamically if not cls._meta.abstract: if self.localized_field_model: for lang_code, lang_name in settings.LANGUAGES: localized_field = self.get_localized_field( lang_code, lang_name) localized_field.contribute_to_class( cls, MultilingualField.localized_field_name( name, lang_code)) setattr(cls, name, property(translated_value)) else: super().contribute_to_class( cls, name, private_only) class MultilingualCharField(models.CharField, MultilingualField): pass class MultilingualTextField(models.TextField, MultilingualField): pass
這裡定義了 MultilingualCharField 和 MultilingualTextField欄位
使用方法
settings.py
中配置多語言
LANGUAGE_CODE = 'zh-hans'
TIME_ZONE = 'Asia/Shanghai'
LANGUAGES = (
('en-us', 'US English'),
('zh-hans', 'Asia/Shanghai')
)
預設語言設定為中文,多語言為英語
models.py
中使用欄位
from django.db import models from django.utils.translation import ugettext_lazy as _ from utils.fields import ( MultilingualCharField, MultilingualTextField ) class Item(models.Model): title = MultilingualCharField(_('Title'), max_length=200) description = MultilingualTextField(_('Description'), blank=True) content = MultilingualTextField(_('Content')) def __str__(self): return self.title
效果圖
可以看到,資料庫欄位自動生成了相應語言的欄位
當用戶語言切換到其他,可以自動適配實現多語