有没有办法为python枚举指定默认值？

有没有办法为python枚举指定默认值？

MyEnum(..)

由处理

Enummeta.__call__

。您需要重写该方法：

from enum import Enummeta, IntEnumclass DefaultEnummeta(Enummeta):    default = object()    def __call__(cls, value=default, *args, **kwargs):        if value is DefaultEnummeta.default: # Assume the first enum is default return next(iter(cls))        return super().__call__(value, *args, **kwargs)        # return super(DefaultEnummeta, cls).__call__(value, *args, **kwargs) # PY2class MyEnum(IntEnum, metaclass=DefaultEnummeta):    # __metaclass__ = DefaultEnummeta  # PY2 with enum34    A = 0    B = 1    C = 2assert MyEnum() is MyEnum.Aassert MyEnum(0) is MyEnum.Aassert MyEnum(1) is not MyEnum.A