如何在Python中的while循环内停止for循环

Question

我正在生成一个简单的运动员比赛时间数据输入表，我需要它询问每个通行证用户是否要继续，如果要继续，则再次进行，如果不继续，则退出while循环。 如果用户未输入至少4-8条数据，则会产生错误，而不是打印时间。 我相信该错误是由于它在第一次通过while循环之后导致的，直到在for循环中执行了8次之后，它才执行另一遍操作。 我将如何解决这个问题。 请解释您的代码，并将其与我提供的上下文相关联。

import time
datasets= []
carry_on = True


while carry_on == True:
    for i in range(0, 8):
        print("Inputting Data for Lane", i)
        gender = str(input("Is the athlete male or female ")) 
        athlete = str(input("What is the athletes name "))
        finishTime = float(input("What was the finishing time "))
        dataset = [gender, athlete, finishTime]
        datasets.append(dataset)
        decision = input("Would you like to add another lane ")
        if decision == "yes":
            carry_on = True
        else:
            carry_on = False

print("")

if 3 < i > 9:
    print("{0:<10}{1:<10}{2:<15}".format("Gender","Athlete","Finish time"))
    ds = sorted(datasets, key=lambda x:x[2], reverse=False)
    for s in ds:
        time.sleep(1)
        print("{0:<10}{1:<10}{2:<15}".format(s[0], s[1], s[2]))
else:
    print("You have not chosen enough lanes, please choose atleast 4")

Answer 1

首先，学习基础

尝试中断for循环，不确定是否需要

for i in range(0, 8):
    print("Inputting Data for Lane", i)
    gender = str(input("Is the athlete male or female ")) 
    athlete = str(input("What is the athletes name "))
    finishTime = float(input("What was the finishing time "))
    dataset = [gender, athlete, finishTime]
    datasets.append(dataset)
    decision = input("Would you like to add another lane ")
    if decision != "yes":
        break

//根据您的代码和您的要求

import time
datasets= []
carry_on = True


while carry_on == True:
    for i in range(0, 8):
        print("Inputting Data for Lane", i)
        gender = str(input("Is the athlete male or female ")) 
        athlete = str(input("What is the athletes name "))
        finishTime = float(input("What was the finishing time "))
        dataset = [gender, athlete, finishTime]
        datasets.append(dataset)
        decision = input("Would you like to add another lane ")
        if decision == "yes":
            carry_on = True
        else:
            carry_on = False
            break

print("")

if 3 < i > 9:
    print("{0:<10}{1:<10}{2:<15}".format("Gender","Athlete","Finish time"))
    ds = sorted(datasets, key=lambda x:x[2], reverse=False)
    for s in ds:
        time.sleep(1)
        print("{0:<10}{1:<10}{2:<15}".format(s[0], s[1], s[2]))
else:
    print("You have not chosen enough lanes, please choose atleast 4")

Answer 2

无论如何，for循环都会执行8次迭代，因此您将始终输入8条通道。 您可以完全删除for循环，并用一个简单的计数器替换它。 当用户选择添加另一个车道时，增加计数器，当它达到8时-结束循环。 类似于（用伪代码）：

counter =0
while carry_on
  <read user input>
  if counter < 8
    <ask user to continue>
  if decision == "yes"
    counter++
    carry_on = true
  else
    carry_on = false
<handle input here>

Answer 3

您只能使用一个for循环和break指令：

for i in range(8):
    print("Inputting Data for Lane", i)
    gender = input("Is the athlete male or female ")
    athlete = input("What is the athletes name ")
    finishTime = float(input("What was the finishing time "))
    dataset = [gender, athlete, finishTime]
    datasets.append(dataset)
    decision = input("Would you like to add another lane ")
    if decision != "yes":
        break

请注意，可以写入range（0，8）：range（8）

输入返回一个字符串，因此str（input（...））是无用的。

此外：

if 3 < i > 9

手段：

if i > 3 and i > 9:

我认为您的意思是：

if 3 < i < 9:

最后：如果用户输入的不是数字，则float（input（...））可能会引发ValueError异常。 您应该添加一个try：except：construct。