字典的增删改查
info = {"name":"Poe"}#增info["age"] = 18info["qq"] = 33794712print(info)
#{'age': 18, 'qq': 33794712, 'name': 'Poe'}#删del info['qq']print(info)
#{'age': 18, 'name': 'Poe'}#如果字典中没有这个键，那么程序会抛出异常#查print(info['name'])
#Poe#如果没有name键会抛出异常print(info.get('name'))
#Poe#如果没有name键不会抛出异常，返回空#改info['name'] = 'andy'print(info)
#{'age': 18, 'name': 'andy'}for else语句nums = [11,22,33,44,55]for temp in nums:
print(nums)else:
print("="*10)#else中的语句是for循环结束后执行有关字典的遍历info = {"name":"poe","age":18,"addr":"Hongkong"}print(len(info))
#3print(info.keys())
#dict_keys(['name', 'addr', 'age'])print(info.values())
#dict_values([18, 'poe', 'Hongkong'])#注：以上是python3得到的结果，python2中只返回其中的列表部分for key in info.keys():
print(key)for value in info.values():
print(value)print(info.items())
#dict_items([('addr', 'Hongkong'), ('name', 'poe'), ('age', 18)])for temp in info.items():
print("key=%s,value=%s" % (temp[0],temp[1]))"""输出结果：key=addr,value=Hongkongkey=age,value=18key=name,value=poe"""
#注意元组的下面这种使用方法a = (11,22)b,c = aprint(b,c)
#11 22for A,B in info.items():
print("key=%s,value=%s" % (A,B))'''输出结果：key=age,value=18key=addr,value=Hongkongkey=name,value=poe'''
