1. 字典的基本操作
1.1 創(chuàng)建一個字典
doer_0 = {"name":"hsy","gender":"male","age":22} #空字典doer_0 = {}
print(doer_0["name"])
hsy
print(doer_0["gender"])
male
print(doer_0["age"])
22
1.2 增加鍵值對
doer_0["hobby"] = "bioinformatics"
print(doer_0)
{'name': 'hsy', 'gender': 'male', 'age': 22, 'hobby': 'bioinformatics'}
1.3 修改鍵的值
doer_0["hobby"] = "Python"
print(doer_0)
{'name': 'hsy', 'gender': 'male', 'age': 22, 'hobby': 'Python'}
1.4 刪除鍵值對
del doer_0["hobby"]
print(doer_0)
{'name': 'hsy', 'gender': 'male', 'age': 22}
1.5 類似對象組成的字典
跟Perl中的哈希表一樣
doers_performance = {"hsy1":"good","hsy2":"very good"}
print(doers_performance)
{'hsy1': 'good', 'hsy2': 'very good'}
2. 遍歷字典
遍歷鍵值對
for key,value in doer_0.items():
print(key)
print(str(value) + "\n------")
name
hsy
------
gender
male
------
age
22
------
遍歷鍵
for key in doer_0.keys():
print(key + "\n------")
name
------
gender
------
age
------
#按順序遍歷
for key in sorted(doer_0.keys()):
print(key + "\n------")
age
------
gender
------
name
------
遍歷值，可使用方法values()；當(dāng)值列表含有重復(fù)元素時蛉签，可使用函數(shù)set()去重顯示噪伊。
3. 字典的嵌套
3.1 在列表中存儲字典
doer_1 = {'name':'xiaoming','gender':'male','age':12}
print(doer_1)
{'name': 'xiaoming', 'gender': 'male', 'age': 12}
doers = [doer_0,doer_1]
print(doers)
[{'name': 'hsy', 'gender': 'male', 'age': 22}, {'name': 'xiaoming', 'gender': 'male', 'age': 12}]
for doer in doers:
print(doer)
{'name': 'hsy', 'gender': 'male', 'age': 22}
{'name': 'xiaoming', 'gender': 'male', 'age': 12}
