Question

class MyDict(dict):
    def __init__(self, *args):
        #fill in here

如何编写构造函数，以便将键“name”设置为“james”。

d = MyDict()
print d['name'] ....this should print out "james"

Answer 1

在（C）Python 2.5.2中：

>>> class MyDict(dict):
...   def __init__(self, *args, **kwargs):
...     super(MyDict, self).__init__(*args, **kwargs)
...     self['name'] = 'james'
...
>>> d = MyDict()
>>> print d['name']
james

Answer 2

dict的基本子类将允许基本存储：

class MyDict(dict):
    def __init__(self, *args):
        super(MyDict, self).__init__(*args, **kwargs)
        self['name'] = 'james'

对于更复杂的存储空间，您可能需要查看__setitem__和__getitem__

我如何正确地子类化“dict”？

2 个答案: