A concise introduction to exception handling in Python _python

The python exception handling mechanism is similar to Java, using a try-except-finally structure.

Try-except Detection exception

Format

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Try
Try_statement
Except (ErrorType1, ErrorType2), E:
Handle_statement
Finally
Finally_statement

Instance

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#!/usr/bin/python
Try
A=12
B=0
c = A/b
Except Exception, E:
Print "Exception occurs:", E
Finally
Print "Finally handle!"

Context Manager (With...as ...) Statement)

The WITH statement can be especially useful when you first open the scenario where the resource was last freed, because it automatically frees up the resources that are in the possession and does not need to be shown to release the resources

Format

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With context_expr [as Var]:
With_statement

raise throws an exception

Format

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Raise exception[, args] or raise Exception (args)

Instance

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Raise Exception (' exampleexception ')

assert

Detects the key point of the program, the assertion is unsuccessful when the trigger Asserterror (assertion error)
Format is as follows

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Assert expression[, arguements]