擅长:python、mysql、java
<p>可以使用<a href="https://docs.python.org/3/library/types.html#types.MappingProxyType" rel="nofollow">^{<cd1>}</a>创建字典的不可变视图:</p>
<pre><code>from types import MappingProxyType
d = { 'a': 1 }
fd = MappingProxyType(d)
fd['a']
#output:
1
fd['a'] = 2
#output:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'mappingproxy' object does not support item assignment
</code></pre>
<p>请注意,您仍然可以更改vaule对象,因此:</p>
^{pr2}$
<p>会有用的。在</p>