blocks|key|185185|text|您可以使用访问名称空间的字典|type|unstyled|depth|inlineStyleRanges|entityRanges|data|185186|>>>+import+argparse
>>>+args+=+argparse.Namespace()
>>>+args.foo+=+1
>>>+args.bar+=+[1,2,3]
>>>+d+=+vars(args)
>>>+d
{'foo':+1,+'bar':+[1,+2,+3]}|code-block|syntax|javascript|185187|如果愿意，您可以直接修改字典：|185188|>>>+d['baz']+=+'store+me'
>>>+args.baz
'store+me'|185189|可以，可以访问__dict__属性。这是一种定义良好、经过测试和保证的行为。|185190|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

You can access the namespace's dictionary with <a href="http://docs.python.org/3/library/functions.html#vars" rel="noreferrer">vars()</a>:

<pre><code>&gt;&gt;&gt; import argparse
&gt;&gt;&gt; args = argparse.Namespace()
&gt;&gt;&gt; args.foo = 1
&gt;&gt;&gt; args.bar = [1,2,3]
&gt;&gt;&gt; d = vars(args)
&gt;&gt;&gt; d
{'foo': 1, 'bar': [1, 2, 3]}
</code></pre>

You can modify the dictionary directly if you wish:

<pre><code>&gt;&gt;&gt; d['baz'] = 'store me'
&gt;&gt;&gt; args.baz
'store me'
</code></pre>

Yes, it is okay to access the __dict__ attribute. It is a well-defined, tested, and guaranteed behavior.

blocks|key|2805079|text|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2805080|“深入”一个对象并使用它的dict属性合适吗？|blockquote|offset|length|style|BOLD|2805081|2805082|2805083|一般来说，我会说“不”。然而，Namespace给我的印象是过度工程，可能是在类不能从内置类型继承的时候。|CODE|2805084|另一方面，Namespace确实为argparse提供了一种面向任务的方法，我想不出有哪种情况需要抓住__dict__，但我的想象力与您的不同。|2805085|entityMap^0|0|D|4|0|0|0|F|9|0|5|9|1F|8|0^^$0|@$1|2|3|-4|4|5|6|Q|7|@]|8|@]|9|$]]|$1|A|3|B|4|C|6|R|7|@$D|S|E|T|F|G]]|8|@]|9|$]]|$1|H|3|-4|4|5|6|U|7|@]|8|@]|9|$]]|$1|I|3|-4|4|5|6|V|7|@]|8|@]|9|$]]|$1|J|3|K|4|5|6|W|7|@$D|X|E|Y|F|L]]|8|@]|9|$]]|$1|M|3|N|4|5|6|Z|7|@$D|10|E|11|F|L]|$D|12|E|13|F|L]]|8|@]|9|$]]|$1|O|3|-4|4|5|6|14|7|@]|8|@]|9|$]]]|P|$]]

<blockquote>
 Is it proper to "reach into" an object and use its dict property?
</blockquote>

In general, I would say "no". However <code>Namespace</code> has struck me as over-engineered, possibly from when classes couldn't inherit from built-in types. 

On the other hand, <code>Namespace</code> does present a task-oriented approach to argparse, and I can't think of a situation that would call for grabbing the <code>__dict__</code>, but the limits of my imagination are not the same as yours.

blocks|key|2805094|text|Straight+from+the+horse's+mouth|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2805095|如果您希望拥有类似字典的属性视图，您可以使用标准的Python惯用法，vars()|style|CODE|2805096|parser+=+argparse.ArgumentParser()+>>>+parser.add_argument('--foo')+>>>+args+=+parser.parse_args('--foo'，‘’)+>>>+vars(args)+{'foo'：‘parser.add_argument’}|blockquote|2805097|2805098|-+Python标准库，16.4.4.6。The+Namespace+object|2805099|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.python.org/3/library/argparse.html#the-namespace-object|1|https://docs.python.org/3/library/functions.html#vars|2^0|0|V|0|0|Z|6|Z|6|1|0|0|0|L|K|2|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]]|C|$]]|$1|D|3|E|5|6|7|12|8|@$A|13|B|14|F|G]]|9|@$A|15|B|16|1|17]]|C|$]]|$1|H|3|I|5|J|7|18|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|19|8|@]|9|@]|C|$]]|$1|L|3|M|5|6|7|1A|8|@]|9|@$A|1B|B|1C|1|1D]]|C|$]]|$1|N|3|-4|5|6|7|1E|8|@]|9|@]|C|$]]]|O|$P|$5|Q|R|S|C|$T|U]]|V|$5|Q|R|S|C|$T|W]]|X|$5|Q|R|S|C|$T|U]]]]

<a href="https://docs.python.org/3/library/argparse.html#the-namespace-object" rel="noreferrer">Straight from the horse's mouth</a>:
<blockquote>
If you prefer to have dict-like view of the attributes, you can use the standard Python idiom, <a href="https://docs.python.org/3/library/functions.html#vars" rel="noreferrer"><code>vars()</code></a>:
<pre><code>&gt;&gt;&gt; parser = argparse.ArgumentParser()
&gt;&gt;&gt; parser.add_argument('--foo')
&gt;&gt;&gt; args = parser.parse_args(['--foo', 'BAR'])
&gt;&gt;&gt; vars(args)
{'foo': 'BAR'}
</code></pre>
— The Python Standard Library, 16.4.4.6. <a href="https://docs.python.org/3/library/argparse.html#the-namespace-object" rel="noreferrer">The Namespace object</a>
</blockquote>

blocks|key|185202|text|请注意，如果您试图将args视为一个字典，以确定它是否具有属性，则可以改为执行以下操作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|185203|if+hasattr(args,+'someProperty'):
++++a.someProperty|code-block|syntax|javascript|185204|有关hasattr和similar+answer+to+another+question的更多信息|offset|length|185205|此外，如果您喜欢使用类似的getattr+method，也可以获取该值|185206|value+=+getattr(args,+'someProperty')|185207|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.python.org/3/library/functions.html#hasattr|1|https://stackoverflow.com/a/610893/26510|2|https://docs.python.org/3/library/functions.html#getattr^0|0|0|2|7|0|A|Y|1|0|D|E|2|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|12|8|@]|9|@$I|13|J|14|1|15]|$I|16|J|17|1|18]]|A|$]]|$1|K|3|L|5|6|7|19|8|@]|9|@$I|1A|J|1B|1|1C]]|A|$]]|$1|M|3|N|5|D|7|1D|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]|W|$5|R|S|T|A|$U|X]]|Y|$5|R|S|T|A|$U|Z]]]]

Note that if you're trying to treat args as a dict to find out if it has an attribute, you can just do the following instead:
<pre><code>if hasattr(args, 'someProperty'):
 a.someProperty
</code></pre>
more info on <a href="https://docs.python.org/3/library/functions.html#hasattr" rel="nofollow noreferrer">hasattr</a> and <a href="https://stackoverflow.com/a/610893/26510">similar answer to another question</a>
Also, you can get the value if you prefer using the similar <a href="https://docs.python.org/3/library/functions.html#getattr" rel="nofollow noreferrer">getattr method</a>:
<pre><code>value = getattr(args, 'someProperty')
</code></pre>

If I want to use the results of <code>argparse.ArgumentParser()</code>, which is a <code>Namespace</code> object, with a method that expects a dictionary or mapping-like object (see <a href="http://docs.python.org/2/library/collections.html#collections.Mapping" rel="noreferrer">collections.Mapping</a>), what is the right way to do it?

<pre><code>C:\&gt;python
Python 2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 bit (Intel)] on win
32
Type "help", "copyright", "credits" or "license" for more information.
&gt;&gt;&gt; import argparse
&gt;&gt;&gt; args = argparse.Namespace()
&gt;&gt;&gt; args.foo = 1
&gt;&gt;&gt; args.bar = [1,2,3]
&gt;&gt;&gt; args.baz = 'yippee'
&gt;&gt;&gt; args['baz']
Traceback (most recent call last):
 File "&lt;stdin&gt;", line 1, in &lt;module&gt;
TypeError: 'Namespace' object has no attribute '__getitem__'
&gt;&gt;&gt; dir(args)
['__class__', '__contains__', '__delattr__', '__dict__', '__doc__', '__eq__', '_
_format__', '__getattribute__', '__hash__', '__init__', '__module__', '__ne__',
'__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__
', '__str__', '__subclasshook__', '__weakref__', '_get_args', '_get_kwargs', 'ba
r', 'baz', 'foo']
</code></pre>

Is it proper to "reach into" an object and use its <code>__dict__</code> property?

I would think the answer is no: <code>__dict__</code> smells like a convention for implementation, but not for an interface, the way <code>__getattribute__</code> or <code>__setattr__</code> or <code>__contains__</code> seem to be.

What is the right way to treat Python argparse.Namespace() as a dictionary?

Python

如果我想将argparse.ArgumentParser() (一个Namespace对象)的结果与一个需要字典或类似映射的对象(请参阅)的方法一起使用，那么正确的方法是什么？C:\>pythonPython 2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 b...

问将Python argparse.Namespace()作为字典对待的正确方式是什么？
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