为什么if语句失败?(初学者)

Question

我的代码有问题。

我的代码是一个初学者的号码猜测器。当用户键入一个字母when时，该代码应该写一个错误。

我首先想到将CCD_ 1转换成整数；它是字符串还是整数；但我意识到这行不通。然后我写了这个。。。在我的脑海中，它应该起作用，但当我写信时，它在if int(usrin_guess) > uo_rand_num:上失败了。

def rand_num(num):
return random.randint(1, num) # Making a random number between the amount of number input and 1
uo_rand_num = rand_num(amount_of_numbers)
while int(usrin_guess) != uo_rand_num:

usrin_guess = input("Enter a number between " + "1" + " and " + usrin_amount_of_numbers + " ") 

try:
val = int(usrin_guess)  
except ValueError:
val_input == False

if val_input == True:
if int(usrin_guess) > uo_rand_num:
print("The number is lower than " + usrin_guess)
elif int(usrin_guess) < uo_rand_num: 
print("The number is higer than " + usrin_guess)
elif int(usrin_guess) == uo_rand_num:
answer = True
usr_guesses += 1
else:
print("Please don't enter a character")

Answer 1

很好的尝试，如果您创建一个像get_int_input这样的辅助函数来处理所有验证，并使用f-string进行字符串插值，这可能会有所帮助：

import random

def get_int_input(prompt: str, min_num: int, max_num: int) -> int:
num = -1
while True:
try:
num = int(input(prompt=prompt))
if min_num <= num <= max_num:
break
print(f'''Error: Integer outside of the allowed range, 
[{min_num}, {max_num}], try again...''')
except ValueError:
print('Error: Enter an integer, try again...')
return num

def rand_num(min_num: int, max_num: int) -> int:
return random.randint(a=min_num, b=max_num)

def guessing_game() -> None:
min_num, max_num = 1, 10
num_to_guess = rand_num(min_num=min_num, max_num=max_num)
attempts = 0
user_guess = -1
while user_guess != num_to_guess:
attempts += 1
user_guess = get_int_input(
prompt=
f'Enter a number between {min_num} and {max_num} inclusive: ',
min_num=min_num,
max_num=max_num)
if user_guess < num_to_guess:
print(f'The number is higher than {user_guess}')
elif user_guess > num_to_guess:
print(f'The number is less than {user_guess}')
attempt_or_attempts = 'attempt' if attempts == 1 else 'attempts'
print(
f'Congrats! You guessed the number in {attempts} {attempt_or_attempts}!'
)

def main() -> None:
guessing_game()

if __name__ == '__main__':
main()

示例用法：

Enter a number between 1 and 10 inclusive: 5
The number is higher than 5
Enter a number between 1 and 10 inclusive: 11
Error: Integer outside of the allowed range, [1, 10], try again...
Enter a number between 1 and 10 inclusive: 7
The number is higher than 7
Enter a number between 1 and 10 inclusive: 9
The number is higher than 9
Enter a number between 1 and 10 inclusive: 10
Congrats! You guessed the number in 4 attempts!

请尝试此处。

Answer 2

尝试将其转换为ASCII值。

您可以使用ord()函数来获取ASCII值。每个字母都有自己的ASCII值，对于A，它是065，而Z的值是090。

因此，为了检查输入是否是字符，或者不只是检查ASCII值是否在该范围之间。ASCII表：http://sticksandstones.kstrom.com/appen.html

Answer 3

最好使用while True循环，并在满足条件时使用循环外的usrin_guess0。这样，您就不必编写两次输入语句。

您可以使用格式化的字符串，而不是字符串上的串联。

您可以直接将代码块放入try和except块中，而不是定义一个变量来检测是否发生错误：

def rand_num(num):
return random.randint(1, num) # Making a random number between the amount of number input and 1
uo_rand_num = rand_num(amount_of_numbers)
usrin_guess = 0
while True:
usrin_guess = input(f"Enter a number between 1 and {usrin_amount_of_numbers} ")
if int(usrin_guess) == uo_rand_num:
break
try:
val = int(usrin_guess)
if int(usrin_guess) > uo_rand_num:
print("The number is lower than " + usrin_guess)
elif int(usrin_guess) < uo_rand_num: 
print("The number is higer than " + usrin_guess)
elif int(usrin_guess) == uo_rand_num:
answer = True
usr_guesses += 1
except ValueError:
print("Please don't enter a character")