Python checks whether the array element has a method similar to PHPisset ().

The isset method checks whether the array element exists. in Python, there is no corresponding function. in Python, exceptions can be used to handle the case where the array element does not exist, the isset method in PHP does not need to be checked beforehand to check whether the array element exists, and no corresponding function exists in Python.

Python's programming philosophy is to "tolerate errors" rather than "strictly check ". Example:

The code is as follows:

Look before you leap (LBYL ):

If idx <len (array ):
Array [idx]
Else:
# Handle this

Easier to ask forgiveness than permission (EAFP ):


Try:
Array [idx]
Failed T IndexError:
# Handle this

Therefore, in Python, exceptions can be used to handle situations where the array element does not exist without prior check.

If you do not want to see exception handling, you can also do the following:

The code is as follows:

If 'Test' in ['demo', 'example ']:

...

Else:

...