在“if”语句中尝试 Python 的“None”，但我无法打印消息：“print(“Any value.!”)”将 None 与空值进行比较，为什么我不能？

Question

value = None

print("Insert a value:")
value = input()

if value == None:
    print("Any value.!")
else:
    print("Your value is different to None: ", value)

Answer 1

When you assign value = input() , value will now be a string. Even if the user does not provide an input (just hits enter), the value will be an empty string '' . So comparing to None will always fail.

Instead, just check if the value is not empty using if value:

print("Insert a value:")
value = input()

if value:
    print("Any value.!")
else:
    print("Your value is different to None: ", value)