CODEWITHSUNDEEP
python
Someone Randumb
Someone Randumb

Reputation: 13

How can i make sure that my user types in a number and not a letter.... Python v3.x.x

age = int(input)

while age > 130 or age < 0:
    print('Please print a valid age')
    age = int(input())

I am trying to make sure that the user doesn't type a letter and make my program crash. Also, I am trying to ask for a valid age between 0 and 130. If values are outside, a message should come up saying, not a valid age and should proceed to rewind the while statement by asking the user to prompt in different values for age

Upvotes: 0

Views: 596

Answers (3)

Mikhail Sidorov
Mikhail Sidorov

Reputation: 1434

input() always considered as string if user inputs non integer it will throw ValueError which can be handled with try and except block as below:

try:
    age = int(input())
    while age > 130 or age < 0:
        print('Please print a valid age')
        age = int(input())
except ValueError:
    print('Please print a valid age')

Upvotes: 0

Primusa
Primusa

Reputation: 13498

Use a try except to handle non-digit inputs. To keep prompting the user for a valid age until they have inputted one just keep your loop on true and only break it when you get a valid age:

print("Please input a valid age")
while True:
    try:
        age = int(input())
        assert 0 < age < 130
        break
    except (AssertionError, ValueError):
        print("Please input a valid age")
print(age)

If you don't want to use try/excepts you can use .isdigit():

print("Please input a valid age")
while True:
    age = input()
    if age.isdigit() and (0 <int(age)< 130): break
    else: print("Please input a valid age")
print(int(age)) #age is valid and you can safely convert to int

Upvotes: 2

Jia
Jia

Reputation: 354

You can do the following. Can I help you? 

def CheckAge(value):
"""Check the user input number"""
return value.isdigit()


def CheckRange(value):
"""Check the number range"""
if int(value) > 0 and int(value) < 130:
    return True


while True:
    age = input('Please enter your age:')

    if CheckAge(age) and CheckRange(ageq):
        break
    else:
        print('Please input a valid age')

Upvotes: 0

Related Questions