有时候枚举类型中比如A.a可以获取到A中a定义的code如a='vehicle'，但是vehicle对应需要展示车辆这个文本
# 1. 定义枚举元类
import inspect
import operator
from enum import Enum
from enum import EnumMeta
from functools import reduce
class BaseEnumMeta(EnumMeta):
""" 枚举元类 """
def __new__(mcs, name, bases, attrs):
Label = mcs.get_meta("Label", attrs)
Code = mcs.get_meta("Code", attrs)
obj = super().__new__(mcs, name, bases, attrs)
mcs.add_to_enum("label", obj, Label)
mcs.add_to_enum("code", obj, Code)
return obj
@classmethod
def get_meta(mcs, meta_name, attrs):
""" 获取元数据 """
meta = attrs.get(meta_name)
if meta is None:
return meta
if inspect.isclass(meta):
del attrs[meta_name]
if hasattr(attrs, '_member_names'):
attrs._member_names.remove(meta_name)
return meta
if inspect.isfunction(meta):
del attrs[meta_name]
return meta
@classmethod
def add_to_enum(mcs, name, obj, meta):
""" 添加属性到枚举值上 """
if inspect.isclass(meta):
for item in obj:
setattr(item, name, getattr(meta, item.name, None))
if inspect.isfunction(meta):
for item in obj:
setattr(item, name, meta(item))
# 2. 为了使用方便，可以再定一个父类实现其他需求
class BaseEnum(Enum, metaclass=BaseEnumMeta):
@classmethod
def has(cls, val):
""" 判断一个值是否合法 """
for item in cls:
if val == item.code:
return True
return False
@classmethod
def from_code(cls, value):
""" 从 Code 构建枚举值 """
return [item for item in cls if item.code == value][0]
class BitFlagEnum(int, BaseEnum, metaclass=BaseEnumMeta):
""" 标志位枚举基类 """
@classmethod
def bit_mask(cls, values):
""" 位掩码 """
return reduce(
operator.or_,
[item for item in cls for val in values if item.code == val],
0
)
@classmethod
def bit_unmask(cls, val):
""" 解析位掩码 """
return [item.code for item in cls if item & val]
# 3. 定义业务实现的枚举类继承上面的父类
class QPrivyFieldsFlag(BitFlagEnum):
"""用户字段标志位"""
NAME = 1
DOCUMENT = 2
PHONE = 4
EMAIL = 8
class Label:
NAME = "姓名"
DOCUMENT = "证件类型·证件号"
PHONE = "手机号"
EMAIL = "邮箱"
def Code(self):
return self.name.lower()
class DocumentType(BaseEnum):
"""用户证件类型"""
id_card = "01"
pass_port = "02"
org_code = "03"
credit_code = "04"
biz_license_code = "05"
class Label:
id_card = "身份证"
pass_port = "护照"
org_code = "组织机构代码"
credit_code = "统一社会信用代码"
biz_license_code = "营业执照注册号"
def Code(self):
return self.value
# 4. 使用效果
>> DocumentType.id_card
<DocumentType.id_card: '01'>
>> DocumentType.id_card.label
'身份证'
>> DocumentType.id_card.name
'id_card'
>> DocumentType.id_card.value
'01'