Python:如果变量是整数或 float 则为真

Question

我正在尝试根据书本作业编写一个小程序，但我无法检测用户的输入是 int/float(对总数的增量)还是 string (返回错误)。我尝试在 add_to_total 变量上使用 .isdigit() 但是当我输入一个 float 时，它会直接跳到 else 代码块。我曾尝试在互联网上搜索，但找不到明确的答案。这是我的代码:

total = 0
print("Welcome to the receipt program!")

while True:
    add_to_total = raw_input("Enter the value for the seat ['q' to quit]: ")
    if add_to_total == 'q':
        print("*****")
        print "Total: $%s" % total
        break
    if add_to_total.isdigit(): #Don't know how to detect if variable is int or float at the same time.
        add_to_total = float(add_to_total)
        total += add_to_total
    else:
        print "I'm sorry, but '%s' isn't valid. Please try again." % add_to_total

如有任何答复，我们将不胜感激。

Answer 1

您始终可以使用try...except 方法:

try:
    add_to_total = float(add_to_total)
except ValueError:
    print "I'm sorry, but '%s' isn't valid. Please try again." % add_to_total
else:
    total += add_to_total

记住:it's easier to ask forgiveness than permission