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David Accomazzo
15,986 PointsHow would I throw a user-friendly error for the number of tickets not being a string?
Code looks like this so far:
try:
num_tickets = input("How many tickets would you like, {}? ".format(name))
num_tickets = int(num_tickets)
# Raise a ValueError if the request is for more tickets than are available
if num_tickets > tickets_remaining:
raise ValueError('There are only {} tickets remaining.'.format(tickets_remaining))
except ValueError as err:
# include the error text in the output
print("Oh no, we ran into an issue. {}. Please try again.".format(err))
How do we throw an error if int(num_tickets) throws a ValueError? I'm not sure what the syntax for that looks like in Python. Currently it just throws the generic error message if num_tickets is a string. I would like to have it throw something like "You must enter a number, not letters, here!"
2 Answers
Steven Parker
230,274 PointsOne way would be to peek at the contents of the message that would be issued, and replace it with a custom message instead:
except ValueError as err:
if ("invalid literal" in str(err)):
# use custom message for bad characters
print("You must enter a number, not letters, here!")
else:
# include the error text in the output
print("Oh no, we ran into an issue. {} Please try again.".format(err))
David Accomazzo
15,986 PointsSounds good to me! Thanks