[Python知识库]九. 基本数据类型-字典

9.1 第一个例子

#!/usr/bin/python3

dict = {}
dict['haha'] = "hehe"
dict[2] = 3343


print (dict['haha'])
print (dict[2])
print (dict)
print (dict.keys())
print (dict.values())

结果：

hehe
3343
{'haha': 'hehe', 2: 3343}
dict_keys(['haha', 2])
dict_values(['hehe', 3343])

9.2 获取字典元素个数

#!usr/bin/python3
d = {"1": "haha", "2": "hehe"}
print("len(d) = ", len(d))

结果：

len(d) = 2

9.3 获取字典的类型

#!usr/bin/python3
dicts = {"1":"haha","2":"ehhehe"}
print("type = ", type(dicts))

结果：

type = <class 'dict'>

9.4 删除字典的值

#!usr/bin/python3
dicts = {"1":"haha","2":"hehehe"}
print("before: ", dicts)
del dicts["1"]
print("after: ", dicts)

结果：

before: ?{'1': 'haha', '2': 'hehehe'}
after: ?{'2': 'hehehe'}

9.5 清空字典

#!usr/bin/python3
dicts = {"1":"haha","2":"hehehe"}
print("before: ", dicts)
dicts.clear()
print("after: ", dicts)

结果：

before: ?{'1': 'haha', '2': 'hehehe'}
after: ?{}

9.6 遍历字典

#!usr/bin/python3
dicts = {"1":"haha", "2":"hehe"}
for key in dicts.keys():
    print(dicts[key])

print("=========================")

for value in dicts.values():
    print(value)

print("=====================")
for key,value in dicts.items():
    print(key + ": " + value)

结果：

haha
hehe
=========================
haha
hehe
=====================
1: haha
2: hehe