问题描述
我有一个带有字典的对象,我想通过 __getitem__ 访问该对象并对其进行迭代(仅值,键无关紧要),但不知道该怎么做.p>
例如:
Python 2.5.2 (r252:60911, Jul 22, 2009, 15:33:10)>>>类库(对象):... def __init__(self):... self.books = {'title':对象,'title2':对象,'title3':对象,}... def __getitem__(self, i):...返回 self.books[i]...>>>图书馆=图书馆()>>>图书馆['标题']<输入对象">>>>图书馆借书:... 打印书...回溯(最近一次通话最后):<module> 中的文件<stdin>"第 1 行文件<stdin>",第 5 行,在 __getitem__ 中关键错误:0>>>
我如何告诉它为字典中的每个项目简单地返回 object (键无关紧要)?
解决方案
def __iter__(self): return self.books.itervalues()
I have an object with a dictionary that I want to access via __getitem__ as well as iterate over (values only, keys don't matter) but am not sure how to do it.
For example:
Python 2.5.2 (r252:60911, Jul 22 2009, 15:33:10) >>> class Library(object): ... def __init__(self): ... self.books = { 'title' : object, 'title2' : object, 'title3' : object, } ... def __getitem__(self, i): ... return self.books[i] ... >>> library = Library() >>> library['title'] <type 'object'> >>> for book in library: ... print book ... Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<stdin>", line 5, in __getitem__ KeyError: 0 >>>
How do I tell it to simply return the object for each item in the dictionary (the key doesn't matter) ?
解决方案
def __iter__(self): return self.books.itervalues()