Question

作为更大的菜单驱动程序的一部分，我想测试用户输入以查看是否输入： 是一个整数 AND 如果是整数，如果它在1到12的范围内，包括。

number = 0    
while True:
    try:
            number = int(input("Enter a whole number between 1 and 12 >>> "))
    except ValueError:
            print("Invlaid input, please try again >>> ")
            continue
    else:   
            if not (1<= number <=12):
                    print("Need a whole number in range 1-12 >>> ")
                    continue
            else:   
                    print("You selected:",number)
                    break

我正在使用Python 3.4.3，并想知道是否有更简洁（更少的行，更好的性能，更多的“Pythonic”，例如）方法来实现这一目标？提前致谢。

Answer 1

如果中的，那么你不需要一个：

while True: try: number = int(input("Enter a whole number between 1 and 12 >>> ")) if 1 <= number <= 12: print("You selected:", number) break print("Need a whole number in range 1-12 >>> ") except ValueError: print("Invlaid input, please try again >>> ")

错误的输入意味着你直接去除了，如果输入是好的并且在你接受的范围内，print("You selected:", number)并且将被执行然后我们中断或者否则print("Need a whole number in range 1-12 >>> ")将被执行超出范围。

Answer 2

您的代码对我来说非常好。小修正（拼写，缩进，不必要的continue）：

while True:
    try:
        number = int(input("Enter a whole number between 1 and 12 >>> "))
    except ValueError:
        print("Invalid input, please try again >>> ")
    else:   
        if 1 <= number <= 12:
            print("You selected: {}".format(number))
            break
        else:
            print("Need a whole number in range 1-12 >>> ")

Answer 3

使用isdigit（）检查非数字字符。那你就不应该抓住异常了。只有一个if并且如果blah包含非数字，它会使用运算符短路来避免执行int（blah）。

while True:
    num_str = raw_input("Enter a whole number between 1 and 12 >>> ")
    if num_str.isdigit() and int(num_str) in range(1,13):
        print("You selected:",int(num_str))
        break
    else:
        print("Need a whole number in range 1-12 >>> ")

Answer 4

我认为您不需要整个try / except阻止。一切都可以融入一个条件：

number = raw_input("Enter a whole number between 1 and 12 >>> ")
while not (number.isdigit() and type(eval(number)) == int and 1<= eval(number) <=12):
    number = raw_input("Enter a whole number between 1 and 12 >>> ")
print("You selected:",number)

检查用户输入以查看它是否满足两个条件

4 个答案: