except
The except
keyword defines a block of code that executes when an error occurs in the associated try block, allowing the program to handle exceptions gracefully.
Syntax
try:
# code that might raise an exception
except:
# code to handle the exception
A specific exception type can also be mentioned as follows:
try:
# code that might raise an exception
except ExceptionType:
# code that runs if the specified exception occurs
Parameters:
ExceptionType
(optional): Specifies the type of exception to catch (e.g.,ValueError
,ZeroDivisionError
).
Return value:
- The except block itself does not return a value.
- It executes code when the associated
try
block raises a matching exception.
Working of the try-except
block
In the try
block, code that might cause an error is executed. If an error occurs, the flow jumps to the except
block to handle it gracefully. Specifying an exception type in except
limits handling to that particular error, allowing for more precise control.
Note: If no exception type is specified, the
except
block will catch all exceptions. It’s best to use specific exception types to avoid unintentionally hiding bugs or critical errors.
Example: Handling Index Error with a General except
Block
This example attempts to access an invalid index in a list, triggering an error that is caught using a general except
block to prevent the program from crashing:
try:array = [0, 1, 2]# list index out of rangen = array[3]except:print('An error occurred.')
The output for this code block will be:
An error occurred.
Codebyte Example
The following example demonstrates how the except
block handles dividing by zero error:
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