python（7）：字典（2）

1.嵌套

将一系列字典存贮再列表中，或将列表作为值存贮在字典中，称为嵌套。可以在列表中嵌套字典，字典中嵌套列表，字典中嵌套字典。

#在列表中存贮字典
dict1 = {'age': 18 , 'height': 175}
dict2 = {'name': 'xiaoming' , 'weight': 130}
dict3 = {'hair': 'black' , 'eye': 'black'}
d = [dict1, dict2, dict3]
for i in d:
    print(i)
{'age': 18, 'height': 175}
{'name': 'xiaoming', 'weight': 130}
{'hair': 'black', 'eye': 'black'}
=========================================
#在字典中存贮列表
pizza = {
    'crust': 'thick',
    'toppings': ['mushrooms', 'extra cheese']
}
print("you ordered a " + pizza['crust'] + '-crust pizza ' + 'with the following toppings:')
for topping in pizza['toppings']:
    print('\t' + topping)
you ordered a thick-crust pizza with the following toppings:
    mushrooms
    extra cheese
favorite_languages = {
    'jen': ['python', 'ruby'],
    'sarach':['c'],
    'edward':['ruby', 'go'],
    'phil':['python', 'c++'],
}
for name,languages in favorite_languages.items():
    print('\n' + name + ' favorite language are:')
    for language in languages:
        print('\t'+ language)
jen favorite language are:
    python
    ruby

sarach favorite language are:
    c

edward favorite language are:
    ruby
    go

phil favorite language are:
    python
    c++
========================
#字典中存贮字典
#首先定义一个名为users的字典，其中包含两个键：用户名'aeinstein'和'mcurie'，与每个键相关联的值都是一个字典，其中包含用户的名，姓，居住地
users = {
    'aeinstein':{
        'first': 'albert',
        'last': 'einstein',
        'location': 'princeton',
    },
    'mcurie':{
        'first': 'marie',
        'last': 'curie',
        'location': 'paris',   
    },
}
for username,user_info in users.items():#遍历字典users,让python依次将每个键存贮在变量username中，并依次将与当前键相关联的字典存贮在变量user_info中
    print('\nusername: ' + username)#打印用户名
    full_name = user_info['first'] + " " + user_info['last']#访问内部字典，变量user_info包含用户信息字典，而该字典包含三个键：'first'，'last'，'location'
    location = user_info['location']
    print('\tfull_name: ' + full_name)
    print('\tlocation: ' + location)
username: aeinstein
    full_name: albert einstein
    location: princeton

username: mcurie
    full_name: marie curie
    location: paris