python - 如何验证变量是否在两个指定数字之间？

如何验证用户输入以将其限制为仅输入-5到-21之间的数值？我目前已经设置了while循环。

while True:
 if flatNumber.isdigit():
      flatNumber = int(flatNumber)
      if flatNumber>5 and flatNumber<21:
           print("Enjoy your stay.")
           break
      else:
           flatNumber = input("Please enter your flat number.")
 else:
    flatNumber = input("Please enter a numerical flat number.")

但是，这只能验证5到21之间的数值吗？有人可以发布解决方案并解释一下如何验证-5到-21之间的数值吗？

最佳答案

您可以使用负值使用简化的链式比较：

if -21 < flatNumber < -5:

str.isdigit不适用于负数，验证输入时，几乎应始终使用try / except：

while True:
    try:
        # try to cast to int
        flatNumber = int(input("Please enter your flat number."))
        # if cast was successful make sure it is in range if not ask again
        if not -21 < flatNumber < -5:
            print("Not in range -5 to -21")
            continue
        break # else all is good break the loop
    except ValueError:
           print("Invalid input")

print(flatNumber)