Python 如何停止使用字符串处理整数的while循环

我正在处理来自用户的整数输入，希望用户通过键入“q”来表示他们已完成输入，从而表明他们已完成输入

以下是我目前的代码： （还是一个初学者，所以不要过分激怒我）

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任何反馈都是有帮助的

运行该代码时，可能会出现

ValueError

。这是python告诉您已经将一个值输入到无法处理该类型值的函数中的方式

检查一下

在本例中，您试图将字母“q”输入到第6行预期为

int（）

的函数中。把

int（）

想象成一台只处理整数的机器。你只是想把一封信塞进一台没有处理信件设备的机器里，而不是突然起火，它拒绝了你的输入，并开始中断

您可能需要将从

str

到

int

的转换包装在一个容器中，以处理异常

def main():
    num = None
    while num != "q":
        num = input("Enter number: ")

        # try handles exceptions and does something with them
        try:
            num = int(num)
        # if an exception of "ValueError" happens, print out a warning and keep going
        except ValueError as e:
            print(f'that was not a number: {e}')
            pass
        
        # if num looks like an integer
        if isinstance (num, (int, float)):
            print('got a number')
    

测试：

---

我将留给您去弄清楚为什么6.02222“不是一个数字。”

尽可能少地更改代码，您应该

def main():
    print("Please enter some numbers. Type 'q' to quit.")
    count = 0
    total = 0
    num=[]
    num.append(input("Enter a number: "))
    while num[-1] != "q":
        num.append(input("Enter a number: "))
        count += 1
        try:
            total += int(num[-1])
        except ValueError as e:
            print('input not an integer')
            break
    print (num)
    print("The average of the numbers is", total / count)
main()

---

您可以通过以下方式尝试：

def main():
    num_list = [] #list for holding in user inputs
    while True:
        my_num = input("Please enter some numbers. Type 'q' to quit.")
        if my_num != 'q':
            num_list.append(int(my_num)) #add user input as integer to holding list as long as it is not 'q'
        else: #if user enters 'q'
            print(f'The Average of {num_list} is {sum(num_list)/len(num_list)}') #calculate the average of entered numbers by divide the sum of all list elements by the length of list and display the result
            break #terminate loop
main() 

看看

def main():
    print("Please enter some numbers. Type 'q' to quit.")
    count = 0
    total = 0
    num=[]
    num.append(input("Enter a number: "))
    while num[-1] != "q":
        num.append(input("Enter a number: "))
        count += 1
        try:
            total += int(num[-1])
        except ValueError as e:
            print('input not an integer')
            break
    print (num)
    print("The average of the numbers is", total / count)
main()

def main():
    num_list = [] #list for holding in user inputs
    while True:
        my_num = input("Please enter some numbers. Type 'q' to quit.")
        if my_num != 'q':
            num_list.append(int(my_num)) #add user input as integer to holding list as long as it is not 'q'
        else: #if user enters 'q'
            print(f'The Average of {num_list} is {sum(num_list)/len(num_list)}') #calculate the average of entered numbers by divide the sum of all list elements by the length of list and display the result
            break #terminate loop
main()