如何使变量在函数中起作用？

Question

我想创建一个存储位置的函数，但是函数中的位置变量变暗了，当运行它说： UnboundLocalError：赋值前引用的局部变量'favPlayer2' 我刚开始使用函数所以..谢谢你的帮助

def position():

    if weight > 80 and height > 190:

        position = 'Center'

        print('Your position is: Center')


    if weight > 80 and height < 190:

        print('Your position is: Power Forward or Small Forward')

        favPlayer = str.lower(input("Favorite player in the list (Lebron James, Jayson Tatum): "))

        while favPlayer != 'lebron james' and favPlayer != 'jayson tatum':

            favPlayer = str.lower(input('Please enter the name correctly: '))

    if favPlayer == 'jayson tatum':

        position = 'Small Forward'

        print('Your position is Small Forward')

    elif favPlayer == 'lebron james':

        position = 'Power Forward'

        print('Your position is Power Forward')



    if weight < 80 and height < 190:

        print('Your position is Point Guard or Shooting Guard')

        favPlayer2 = str.lower(input("Favorite player in the list (Chris Paul, Klay Thompson): "))

        while favPlayer2 != 'chris paul' and favPlayer2 != 'klay thompson':

            favPlayer2 = str.lower(input('Please enter the name correctly: '))

    if favPlayer2 == 'chris paul':

        position = 'Point Guard'

        print('Your position is Point Guard')

    if favPlayer2 == 'klay thompson':

        position = 'Shooting Guard'

        print('Your position is Shooting Guard')
position()

Answer 1

缩进一些 if 块以确保变量已定义

您可以提供一个全局变量，或传递 return 来自函数的值。但是既然你一直没有位置，我就用一个全局变量。

weight = int(input("Enter your weight: "))
height = int(input("Enter your height: "))

position = None

def get_position():
    global position

    if weight > 80 and height > 190:

        position = 'Center'

        print('Your position is: Center')


    if weight > 80 and height < 190:

        print('Your position is: Power Forward or Small Forward')

        favPlayer = str.lower(input("Favorite player in the list (Lebron James, Jayson Tatum): "))

        while favPlayer != 'lebron james' and favPlayer != 'jayson tatum':

            favPlayer = str.lower(input('Please enter the name correctly: '))

        # indented to make sure 'favPlayer' is defined before the if statement
        if favPlayer == 'jayson tatum':

            position = 'Small Forward'

            print('Your position is Small Forward')

        elif favPlayer == 'lebron james':

            position = 'Power Forward'

            print('Your position is Power Forward')



    if weight < 80 and height < 190:

        print('Your position is Point Guard or Shooting Guard')

        favPlayer2 = str.lower(input("Favorite player in the list (Chris Paul, Klay Thompson): "))

        while favPlayer2 != 'chris paul' and favPlayer2 != 'klay thompson':

            favPlayer2 = str.lower(input('Please enter the name correctly: '))

        if favPlayer2 == 'chris paul':

            position = 'Point Guard'

            print('Your position is Point Guard')

        if favPlayer2 == 'klay thompson':

            position = 'Shooting Guard'

            print('Your position is Shooting Guard')

get_position()
print(position)

输出：

Enter your weight: 10 
Enter your height: 29
Your position is Point Guard or Shooting Guard
Favorite player in the list (Chris Paul, Klay Thompson): Chris Paul
Your position is Point Guard

如何使变量在函数中起作用？

how to make a variable work in a function?

python

function

helper