19.2 Try/Except

Try/Except

Similar to if/else, try/except has a first statement, try, and a second statement, except. However, using try/except allows you to deal with errors without crashing your program.

try is the keyword that allows you to test a block of code for errors. All you need to do is type try: and remember to indent the next line of code

except is the keyword that allows you to run a certain set of code if an error was raised in the try part. All you need to do is type except:, although there is more that you could add before the colon. We will get into that later.


try:
	x = 1
	y = "hi"
	x + y #this causes the error
except:
	print("uh oh, something went wrong")

In this example, the except will run because an error was thrown when adding an integer, x, with a string, y. However, x and y will still exist because, when using try/except, all the lines of code before the error will run (try stops running code at the first error, then goes to the except). This means that I could still access x and y if I needed to.

Practice

Integer Checker

Create a program that asks the user to input an integer. Try to convert that into an integer. If it doesn’t work, send the user a message telling them to input an actual integer next time.

💻 Template code

✅ Solution code

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19.1 Intro to Exception Handling

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19.3 Exceptions

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