Question

How can exception handling be used to detect whether an input is a string or an integer?

1) By using the try-except block to catch the ValueError exception
2) By using the if-else statement to check the type of the input
3) By using the assert statement to validate the input
4) By using the isinstance() function to determine the data type of the input

Answer 1

The preferred method to check if an input is a string or an integer is by using a try-except block to catch a ValueError which indicates the input is not an integer. Thus, correct answer is option 1.

Step-by-step explanation:

To detect whether an input is a string or an integer, option 1) 'By using the try-except block to catch the ValueError exception' can be used. Here is a step-by-step explanation:

1. Create a try block where you attempt to convert the input to an integer using the int() function.
2. If the conversion is successful, then the input can be considered as an integer.
3. If the conversion fails, a ValueError exception will be raised.
4. Use an except block to catch the ValueError exception, which indicates that the input is not an integer and is likely a string.

Option 4) 'By using the isinstance() function' can be directly used to determine the data type of the input without exception handling, while options 2) and 3) are not standard methods for this purpose.