March 2022
Intermediate to advanced
522 pages
13h 52m
Chinese
Content preview from Python语言及其应用（第2版）
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98
第 8 章
字典和集合
我们怎么才能知道字典中的某个词拼写错了呢？
——
Steven W
right
8.1
字典
字典
类似于列表，但字典项的顺序并不重要，而且也不是按照
0
或
1
这样的偏移来选择
的。你需要指定与每个
值
关联的不重复的
键
。键多是字符串，但实际上也可以是任何
Python
的不可变类型
：布尔值、整数、浮点数、元组、字符串等。因为字典是可变的，所
以可以添加、删除、修改字典中的键
–
值元素
。如果你用过的语言只支持数组或列表，那
你一定会爱上字典的。
在其他语言中，字典也叫作
关联数组
、
哈希
或
哈希图
。在
Python
中，字典
（
dictionary
）也简称为
dict
。
8.1.1
使用
{}
创建字典
要想创建字典，可以将以逗号分隔的一系列
key
:
value
对放入花括号（
{}
）内。不包含任
何键或值的空字典是最简单的字典：
>>> empty_dict = {}
>>> empty_dict
{}
字典和集合
｜
99
下面来创建一个小字典，其中包含一些取自
Ambrose Bierce
所著的《魔鬼词典》（
The
Devil’s Dictionary
）的引文：
>>> bierce = {
... "day": "A period of twenty-four hours, mostly misspent",
... ...
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