Get started learning Python with DataCamp's free Intro to Python tutorial. Learn Data Science by completing interactive coding challenges and watching videos by expert instructors. Start Now!
This site is generously supported by DataCamp. DataCamp offers online interactive Python Tutorials for Data Science. Join 11 million other learners and get started learning Python for data science today!
Good news! You can save 25% off your Datacamp annual subscription with the code LEARNPYTHON23ALE25 - Click here to redeem your discount
字典
字典是一种类似于数组的数据类型，但使用键和值而不是索引。在字典中存储的每个值都可以通过键来访问，键可以是任意类型的对象（字符串、数字、列表等），而不是通过索引来进行访问。
例如，电话号码数据库可以使用字典来存储，如下所示：
phonebook = {}
phonebook["John"] = 938477566
phonebook["Jack"] = 938377264
phonebook["Jill"] = 947662781
print(phonebook)
或者，一个字典可以使用以下表示法进行初始化：
phonebook = {
"John" : 938477566,
"Jack" : 938377264,
"Jill" : 947662781
}
print(phonebook)
在字典中迭代
字典可以像列表一样进行迭代。然而，与列表不同，字典不保持其中存储值的顺序。要迭代键值对，请使用以下语法：
phonebook = {"John" : 938477566,"Jack" : 938377264,"Jill" : 947662781}
for name, number in phonebook.items():
print("Phone number of %s is %d" % (name, number))
移除一个值
要移除指定的索引，可以使用以下任一种表示法：
phonebook = {
"John" : 938477566,
"Jack" : 938377264,
"Jill" : 947662781
}
del phonebook["John"]
print(phonebook)
或：
phonebook = {
"John" : 938477566,
"Jack" : 938377264,
"Jill" : 947662781
}
phonebook.pop("John")
print(phonebook)
练习
将“Jake”添加到电话簿中，其电话号码为938273443，并从电话簿中删除Jill。
phonebook = {
"John" : 938477566,
"Jack" : 938377264,
"Jill" : 947662781
}
# your code goes here
# testing code
if "Jake" in phonebook:
print("Jake is listed in the phonebook.")
if "Jill" not in phonebook:
print("Jill is not listed in the phonebook.")
phonebook = {
"John" : 938477566,
"Jack" : 938377264,
"Jill" : 947662781
}
# your code goes here
phonebook["Jake"] = 938273443
del phonebook["Jill"]
# testing code
if "Jake" in phonebook:
print("Jake is listed in the phonebook.")
if "Jill" not in phonebook:
print("Jill is not listed in the phonebook.")
test_output_contains("Jake is listed in the phonebook.")
test_output_contains("Jill is not listed in the phonebook.")
success_msg("Nice work!")
This site is generously supported by DataCamp. DataCamp offers online interactive Python Tutorials for Data Science. Join over a million other learners and get started learning Python for data science today!
