在定义的函数中使输入从字符串变为整数。

Question

这是我当前的代码，但是输入不会更改为整数，有人能帮我吗

score = [0,20,40,60,80,100,120] 

def validate_credits(input_credits):
    try:
        input_credits = int(input_credits)
    except:
        raise ValueError('integer required')
        
    if input_credits not in score:
        raise ValueError('out of range')
        
while True: 
    try: 
        mark1 = input('Enter your total PASS marks: ')
        validate_credits(mark1)
    
        mark2 = input('Enter your total DEFER marks: ')
        validate_credits(mark2)
    
        mark3 = input('Enter your total FAIL marks: ')
        validate_credits(mark3)
        
    except ValueError as e: 
           print(e)

Answer 1

这是一个范围界定的问题。考虑：

def the_function(_the_input):
    _the_input = int('2')

if __name__ == "__main__":
    the_input = '1'
    the_function(the_input)
    print(the_input)

你认为the_input会是什么？'1‘或2’？

输出为'1'

一份名单怎么样？

def the_function(_the_input):
    _the_input.append('2')

if __name__ == "__main__":
    the_input = ['1']
    the_function(the_input)
    print(the_input)

输出为['1', '2']

冒着没有正确解释这个问题的风险，我建议你去看this thread on the topic

要将输入作为整数，需要返回以下值：

def the_function(_the_input):
    # + other function logic...
    return int(_the_input)

if __name__ == "__main__":
    the_input = '1'
    the_input = the_function(the_input)
    print(the_input)