Python常量工具类，,1.定义常量类con

Python常量工具类，,1.定义常量类con

1.定义常量类constant.py

# -*- coding: utf-8 -*"""常量工具类author: Jillusage：    from constant import _Const    const = _Const()    const.PI = 3.14"""class _Const:    class ConstError(TypeError):        pass    class ConstCaseError(ConstError):        pass    def __setattr__(self, name, value):        if name in self.__dict__:            raise self.ConstError("Can‘t change const(%s) value" % name)        if not name.isupper():            raise self.ConstCaseError("Const name %s is not all uppercase" % name)        self.__dict__[name] = value    def __getitem__(self, key):        if key in self.__dict__:            return self.__dict__[key]        else:            raise self.ConstError("Can‘t return const %s, No Existing Key!" % key)    def __delattr__(self, name):        if name in self.__dict__:            raise self.ConstError("Can‘t unbind const(%s)" % name)        raise NameError(name)

2.将常量放在一个模块中common_constant.py

# -*- coding: utf-8 -*"""常用常量定义author: Jillusage：    from common_constant import const    print(const.ROOT_PATH)"""from common.constant import _Constconst = _Const()const.PI = 3.14if __name__ == "__main__":    print(const.PI)    print(const[‘PI‘])

3.在其他模块里使用test.py

from common_constant import const    print(const.ROOT_PATH)

Python常量工具类