检查变量是否是Python中的数字[重复]

Question

我正在构建一个预算工具。如果用户输入了错误的预算数字，整个程序就会崩溃并给出错误消息。我想添加一个循环或其他东西让程序循环回来并再次提出问题，而不是在给出无形信息时崩溃。我试过while循环，但它似乎不起作用

while answer != "yes" or answer == "Yes" or answer == "YES":
   print("Hmmm, okay. Try again.")
   answer = input("Ready to budget your travel expenses? ")

budget = int(input("What's your budget? $")**

Answer 1

将输入改为while True 循环，并在获得所需输入后使用break。这是一个简单的例子：

while True:
     answer = input("Ready to budget your travel expenses? ")
     if answer.lower() == "yes":
         break
     print("Hmmm, okay.  Try again.")

while True:
    try:
        budget = int(input("What's your budget? $"))
        break
    except ValueError:
        print("Nope, that's not a number.")