字典操作

info={'xihuan01':'张艺兴','xihuan02':'李易峰','xihuan03':'吴亦凡','xihuan04':'黄景瑜','xihuan05':'朴灿烈','xihuan06': '张云龙'
}
print(info)
print(info['xihuan03'])
info['xihuan03']='like吴亦凡'
print(info)
print(info.get('xihuan05'))#提取元素
print(info.get('xihuan07'))#若元素不存在，返回false
print('xihuan04' in info)#判断元素是否存在

运行结果
{'xihuan01': '张艺兴', 'xihuan02': '李易峰', 'xihuan03': '吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈', 'xihuan06': '张云龙'}
吴亦凡
{'xihuan01': '张艺兴', 'xihuan02': '李易峰', 'xihuan03': 'like吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈', 'xihuan06': '张云龙'}
朴灿烈
None
True

del info['xihuan02']
print(info)
info.pop('xihuan06')
print(info)
info.popitem()  #随意删除
print(info)运行结果
{'xihuan01': '张艺兴', 'xihuan03': 'like吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈', 'xihuan06': '张云龙'}
{'xihuan01': '张艺兴', 'xihuan03': 'like吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈'}
{'xihuan01': '张艺兴', 'xihuan03': 'like吴亦凡', 'xihuan04': '黄景瑜'}
In [ ]:​

actor={'中国':{'何以笙箫默':'钟汉良','微微一笑很倾城':'杨洋','杉杉来了':'张翰'},'韩国':{'太阳的后裔':['宋钟基','宋慧乔'],'W两个世界':['李钟硕','朴信惠'],'坏家伙们':'朴海镇'}
}
print(actor)
actor['韩国']['太阳的后裔'][1]='乔妹'
print(actor)输出
{'中国': {'何以笙箫默': '钟汉良', '微微一笑很倾城': '杨洋', '杉杉来了': '张翰'}, '韩国': {'太阳的后裔': ['宋钟基', '宋慧乔'], 'W两个世界': ['李钟硕', '朴信惠'], '坏家伙们': '朴海镇'}}
{'中国': {'何以笙箫默': '钟汉良', '微微一笑很倾城': '杨洋', '杉杉来了': '张翰'}, '韩国': {'太阳的后裔': ['宋钟基', '乔妹'], 'W两个世界': ['李钟硕', '朴信惠'], '坏家伙们': '朴海镇'}}

info={'xihuan01':'张艺兴','xihuan02':'李易峰','xihuan03':'吴亦凡','xihuan04':'黄景瑜','xihuan05':'朴灿烈','xihuan06': '张云龙'
}
a=info.values()#打印所有的值
print(a)
b=info.keys()#打印所有的key
print(b)
info.setdefault('xihuan06','陈立农')#查找key（xihuan07）如果key存在，返回原来的值，如果不存在，创建新的key-value
print(info)
info.setdefault('xihuan07','陈立农')#查找key（xihuan07）如果key存在，返回原来的值，如果不存在，创建新的key-value
print(info)执行结果
dict_values(['张艺兴', '李易峰', '吴亦凡', '黄景瑜', '朴灿烈', '张云龙'])
dict_keys(['xihuan01', 'xihuan02', 'xihuan03', 'xihuan04', 'xihuan05', 'xihuan06'])
{'xihuan01': '张艺兴', 'xihuan02': '李易峰', 'xihuan03': '吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈', 'xihuan06': '张云龙'}
{'xihuan01': '张艺兴', 'xihuan02': '李易峰', 'xihuan03': '吴亦凡', 'xihuan04': '黄景瑜', 'xihuan05': '朴灿烈', 'xihuan06': '张云龙', 'xihuan07': '陈立农'}

info={'xihuan01':'张艺兴','xihuan02':'李易峰',
}
yyy={'xihuan01':'陈立农','xihuan03':'吴亦凡','xihuan04':'黄景瑜',}
info.update(yyy)#将yyy添加到info，如果存在相同的key，则覆盖，否则添加
print(info)执行结果
{'xihuan01': '陈立农', 'xihuan02': '李易峰', 'xihuan03': '吴亦凡', 'xihuan04': '黄景瑜'}

info={'xihuan01':'张艺兴','xihuan02':'李易峰',
}
print(info.items())#将字典转化为元祖

执行结果>>>
dict_items([('xihuan01', '张艺兴'), ('xihuan02', '李易峰')])

初始化一个字典
c=dict.fromkeys([1,2,3],'test1')
print(c)
执行结果
{1: 'test', 2: 'test', 3: 'test'}c=dict.fromkeys([1,2,3],['test1','test2','test3'])
print(c)执行结果
{1: ['test1', 'test2', 'test3'], 2: ['test1', 'test2', 'test3'], 3: ['test1', 'test2', 'test3']}c[3][1]='ok'#改一个全改了
print(c)
执行结果
{1: ['test1', 'ok', 'test3'], 2: ['test1', 'ok', 'test3'], 3: ['test1', 'ok', 'test3']}

方法一
info={'xihuan01':'张艺兴','xihuan02':'李易峰','xihuan03':'吴亦凡','xihuan04':'黄景瑜','xihuan05':'朴灿烈'
}
for i in info:print(i,info[i])
执行结果
xihuan01 张艺兴
xihuan02 李易峰
xihuan03 吴亦凡
xihuan04 黄景瑜
xihuan05 朴灿烈方法二
for k,v in info.items():print(k,v)
执行结果
xihuan01 张艺兴
xihuan02 李易峰
xihuan03 吴亦凡
xihuan04 黄景瑜
xihuan05 朴灿烈