没有足够的值从字典项中解包：预期 3 个值，得到 2 个

Question

每当我运行这段代码时，python 都会给我：

ValueError: not enough values to unpack (expected 3, got 2)

我正在尝试制作一种地址簿，您可以在其中添加、删除和更改信息。我试图更改第 20 行的代码，其中有一个 for-in 循环（这一行实际上是问题的根源）但它没有给出任何结果。

members = {}

class Member:
    def __init__(self, name, email, number):
        self.name = name
        self.email = email
        self.number = number

    def addmember(name, email, number):
        members[name] = email, number
        print('Member {0} has been added to addressbook'.format(name))

    def Check():
        print("You've got {0} members in your addressbook".format(len(members)))
        for name, email, number in members.items(): #the problem is here
            print('Contact {0} has email:{1} and has number:{2}'.format(name, email, number))
            print('')

Member.addmember('Tim', 'email@mail.com', '43454')
Member.Check()

Answer 1

该错误几乎可以告诉您发生了什么：您正在尝试从列表中解压 3 项，但 members.items() 返回 dict_items class of key-value对，每对看起来像

('Tim', ['email@mail.com', '43454'])

您可以使用

name, info in members.items()

其中 info 是 (email, number) 或

的元组

name, (email, number) in members.items()

将值元组直接解包为两个不同的变量。

没有足够的值从字典项中解包：预期 3 个值，得到 2 个

Not enough values to unpack from dictionary items: expected 3 values, got 2

python

tuples

python-3.x

iterable-unpacking