使用太多“while True:”循环？

Question

我的代码将在下面。我正在练习 Python，想做一个简单的餐厅小费计算器。它工作正常，但我觉得我过于依赖 while 循环。对于每个输入提示，我想让脚本检查输入是否为 int/float，如果不是，它将继续循环，直到给出正确的输入。

是否有人对这是否是进行此类“检查”的好方法有建议？

还有：

在我将“#DETERMINING TIP PERCENTAGE BASED ON QUALITY”和后面的部分放在他们自己的 while 循环中（它们最初是在代码末尾而不是循环中）之前，我无法让脚本移动在“您的服务质量如何？”之后的那些部分。部分。该脚本仅循环播放该部分。知道为什么吗？它的格式似乎与之前的其他 2 个 while 循环完全相同。

谢谢大家。这是我的代码：

while True :
    try :
        total = float(input('Enter the total cost of the meal: '))
        if total < 1 :
            print('Please enter a value greater than 0. ')
            continue
    except :
        print('Please enter a numerical value. ')
        continue

    while True :
        try :
            guests = int(input('How many guests? '))
            if guests < 1 :
                print('Please enter a value greater than 0. ')
                continue
        except :
            print('Please enter a numerical value. ')
            continue

        while True :
            try :
                quality = int(input('How was the quality of your service? 1 - 3: '))
                if quality > 3 or quality < 1 :
                    print('Please enter a value between 1 and 3. ')
                    continue
            except :
                print('Please enter a numerical value. ')
                continue

            #DETERMINING TIP PERCENTAGE BASED ON QUALITY
            while True :
                if quality == 1 :
                    tip_percent = 0.15
                elif quality == 2 :
                    tip_percent = 0.20
                elif quality == 3 :
                    tip_percent = 0.25

                #CALCULATING PER PERSON TIP AMOUNT
                gross_tip = total * tip_percent
                perperson_tip = (total / guests) * tip_percent

                #PRINTING TIP PER PERSON AND GROSS TIP
                print('Per-person tip: ' + str(perperson_tip) + '\nGross tip: ' + str(gross_tip))
                exit()

Answer 1

您的主要问题是您的所有 while 循环都相互嵌套。没有充分的理由。

while True:
  try:
    total = float(input('Enter the total cost of the meal: '))
  except:
    print('Please enter a numerical value.')
    continue
  if total < 1:
    print('Please enter a value greater than 0.')
    continue
  break

while True:
  try:
    guests = int(input('How many guests? '))
  except:
    print('Please enter a numerical value. ')
    continue
  if guests < 1:
    print('Please enter a value greater than 0. ')
    continue
  break

# and so on

Answer 2

您可以使用您的接受条件来打破while 内的循环。 那么你可以完全避免明确的break 和continue 和奇怪的无尽while True。

total = 0
while total < 1:
    try :
        total = float(input('Enter the total cost of the meal: '))
        if total < 1 :
          print('Please enter a value greater than 0. ')
    except :
        print('Please enter a numerical value. ')

guests = 0
while guests < 1:
    try :
        guests = int(input('How many guests? '))
        if guests < 1 :
            print('Please enter a value greater than 0. ')
    except :
        print('Please enter a numerical value. ')

quality = 0
while quality > 3 or quality < 1  :
    try :
        quality = int(input('How was the quality of your service? 1 - 3: '))
        if quality > 3 or quality < 1 :
            print('Please enter a value between 1 and 3. ')
    except :
        print('Please enter a numerical value. ')



if quality == 1 :
    tip_percent = 0.15
elif quality == 2 :
    tip_percent = 0.20
elif quality == 3 :
    tip_percent = 0.25

#CALCULATING PER PERSON TIP AMOUNT
gross_tip = total * tip_percent
perperson_tip = (total / guests) * tip_percent

#PRINTING TIP PER PERSON AND GROSS TIP
print('Per-person tip: ' + str(perperson_tip) + '\nGross tip: ' + str(gross_tip))