Multiple except
- Python course
- Intermediate
- Lesson 82/116
- 5 min
Learn multiple except blocks.
Multiple except blocks
Some operations can throw different kinds of errors. You can write several except clauses under a single try block; Python picks the first match for the error that occurred.
For example int("abc") raises ValueError, division by zero raises ZeroDivisionError. You can catch each in its own except block and show a specific message for each case. Unmatched error types are not caught and propagate up.
Matching order
except blocks are evaluated top to bottom. You should put the more general one (for example Exception) last; otherwise more specific types never get caught. Because Exception covers nearly all errors.
The right order: specific types first (ValueError, TypeError), then Exception. If you break this rule Python still runs but the right message isn't shown for specific error types; the general block always runs.
Practice Write two except blocks
In a try block call value = int("abc"). Below it add two except blocks: first except ValueError: with print("Value error"), second except ZeroDivisionError: with print("Division by zero error"). The call int("abc") raises ValueError; so the first block runs.
Starter code
# Try a number conversion in a try block
# Write two except blocks for ValueError and ZeroDivisionErrorSample solution
# Call int("abc") in a try block
try:
value = int("abc")
# Write two except blocks for ValueError and ZeroDivisionError
except ValueError:
print("Value error")
except ZeroDivisionError:
print("Division by zero error")Expected output
Value error
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What happens with multiple except in one try?
- An error is raised
- The first matching except runs, the rest are skipped Correct answer
- Only the last except runs
- All run in order
Explanation: Python picks the first match top to bottom.
2 Complete the except block
try:
value = int("abc")
____ ValueError:
print("Value error")try:
value = int("abc")
except ValueError:
print("Value error")Explanation: The except keyword starts error handling.
3 Match the exception types
| Term | Meaning |
|---|---|
ValueError |
Invalid value |
TypeError |
Wrong type |
ZeroDivisionError |
Division by zero |
KeyError |
Missing key |