Question

我是Python的新手，目前正在学习函数。我创建了一个简单的程序，询问用户一些信息，然后打印出来。但是，我在将return变量从一个函数链接到另一函数中的print()语句时遇到问题。这是我到目前为止的内容：

def ask_data():
    name = input("What's your name?: ")
    last_name = input("What's your last name?: ")
    age = input("how old are you?: ")
    return(name, last_name, age)

def print_data(data):
    print("Your name is ", name, last_name)
    print("and you are ", age, "years old")

def main():
    data = ask_data()
    print_data(data)

main()

我的问题是我可以输入所有信息，这意味着ask_data()在工作。但是，当调用print_data()时，出现错误，提示找不到变量name，last_name和age。如果出现问题，如何链接两个功能？

Answer 1

您已经关闭。要记住的是，在main函数中，变量data引用了一个元组，因此在print_data中，您实际上不能引用name，last_name，和age直接。您必须先“解包”元组中的值，如下所示：

def print_data(data):
    name, last_name, age = data
    print("Your name is ", name, last_name)
    print("and you are ", age, "years old")

要记住的是，在函数中声明的变量保留在该函数中。 name中的变量ask_data保留在ask_data中。您将所有值包装在一个元组中并返回该值，然后将该元组传递给print_data（很好！），但是print_data不知道这些值的原始名称是正确的。您必须在print_data内创建 new 变量，因为局部变量的名称对于定义它们的每个函数都是“私有的”。

Answer 2

因为您在data和函数def print_data()中的变量不知道：名称，姓氏和 age

示例：

def print_data(data):
    print("Your name is ", data[0], data[1])
    print("and you are ", data[2], "years old")

其中data [0]是您的名称，data [1]是 last_name 和data [2]中的最后一个 age 。

Answer 3

问题是运行脚本时出现错误NameError: name 'name' is not defined。这是因为您需要执行元组拆包。您可以在this Stack Overflow question中找到出色的示例。

要使脚本正常工作，您可以在任何阶段执行解压缩。最简单的修改如下：

def ask_data():
    name = input("What's your name?: ")
    last_name = input("What's your last name?: ")
    age = input("how old are you?: ")
    return(name, last_name, age)

def print_data(data):
    # This will unpack 'data' and make those variables available
    name, last_name, age = data
    print("Your name is ", name, last_name)
    print("and you are ", age, "years old")

def main():
    data = ask_data()
    print_data(data)

main()

产生完全相同结果的另一种方法如下：

def ask_data():
    name = input("What's your name?: ")
    last_name = input("What's your last name?: ")
    age = input("how old are you?: ")
    return(name, last_name, age)

def print_data(name, last_name, age):  # Giving the function new parameters
    print("Your name is ", name, last_name)
    print("and you are ", age, "years old")

def main():
    name, last_name, age = ask_data()  # Unpacking outside the function
    print_data(name, last_name, age)

main()

Answer 4

您可以在函数中使用参数解压缩。看看here。

您将获得以下内容：

def print_data(name, last_name, age):
    ...

def main():
    data = ask_data()
    print_data(*data)

Answer 5

我会使用全局语句

def ask_data():
    global name, last_name, age
    name = input("What's your name?: ")
    last_name = input("What's your last name?: ")
    age = input("how old are you?: ")
    return(name, last_name, age)

def print_data(data):
    global name, last_name, age
    print("Your name is ", name, last_name)
    print("and you are ", age, "years old")

def main():
    global name, last_name, age
    data = ask_data()
    print_data(data)

main()

Answer 6

def ask_data():
    return name, last_name, age
name = input("What's your name?: ")           # i indented your variable to the same line as the funtion "ask_data" 
last_name = input("What's your last name?: ") #reason: so that any of your funtion (e.g. print_data) below can access them
age = input("how old are you?: ")             # you can bring these variable above "def ask_data" if you want.

def print_data(data):                         # in this program you don't need the 1 argument "data". "print_data()" is enough
    print("Your name is ", name, last_name)  # reason: data is not defined, 
    print("and you are ", age, "years old")

def main():
    ask_data()
    print_data("data") # because the word data has not been define, (your can only use it as a string to call print_data
                     # like this print_data("data"). if it was defined, then you can call it as a variable without " ".

main()


my input:
       What's your name?: Simon
       What's your last name?: cigar
       how old are you?: 35

output:
       Your name is  Simon cigar
       and you are  35 years old

链接来自不同函数的变量以打印它们

6 个答案: