Loop Until An Input Is Of A Specific Type

I'm trying to make a program that repeatedly asks an user for an input until the input is of a specific type. My code: value = input('Please enter the value') while isinstance(val

Solution 1:

The reason your code doesn't work is because input() will always return a string. Which will always cause isinstance(value, int) to always evaluate to False.

You probably want:

value = ''whilenot value.strip().isdigit():
     value = input("Please enter the value")

Solution 2:

Be aware when using .isdigit(), it will return False on negative integers. So isinstance(value, int) is maybe a better choice.

I cannot comment on accepted answer because of low rep.

Solution 3:

input always returns a string, you have to convert it to int yourself.

Try this snippet:

whileTrue:
    try:
        value = int(input("Please enter the value: "))
    except ValueError:
        print ("Invalid value.")
    else:
        break

Solution 4:

If you want to manage negative integers you should use :

value = ''whilenot value.strip().lstrip("-").isdigit():
    value = input("Please enter the value")