[自定义字典映射类型]非字符串键转字符串#python

StrKeyDict.py

import collections


class StrKeyDict0(dict):   # 继承dict
    def __missing__(self, key):
        if isinstance(key, str):  # 找不到的键是字符串，抛出keyerror异常
            raise KeyError(key)
        return self[str(key)]  # 找不到的键转为字符串再查找
    def get(self, key, default=None):
        try:
            return self[key]  # 调用__getitem__，找不到会调用__missing__方法
        except KeyError:
            return default    # 如果抛出KeyError异常，说明__missing__方法也查找失败
    def __contains__(self, key):
        return key in self.keys() or str(key) in self.keys()  # 先根据传入键的原本值查找，再转为str键查找
    
class StrKeyDict(collections.UserDict):  # self.data是存储数据的地方
    def __missing__(self, key):
        if isinstance(key, str):
            raise KeyError(key)
        else:
            return self[str(key)]
    
    def __setitem__(self, key, item): # 把key都以字符串形式存储，存在self.data中
        self.data[str(key)] = item

    def __contains__(self, key):
        return str(key) in self.data