Matching Regex Objects A
Regex
object’s
search()
method searches the string it is passed for any
matches to the regex. The
search()
method will return
None
if the regex pat-
tern is not found in the string. If the pattern is found, the
search()
method
returns a
Match
object, which have a
group()
method that will return the
actual matched text from the searched string. (I’ll explain groups shortly.)
For example, enter the following into the interactive shell:
>>> phoneNumRegex = re.compile(r'\d\d\d-\d\d\d-\d\d\d\d') >>> mo = phoneNumRegex.search('My number is 415-555-4242.') >>> print('Phone number found: ' + mo.group()) Phone number found: 415-555-4242
The
mo
variable name is just a generic name to use for
Match
objects.
This example might seem complicated at first, but it is much shorter than
the earlier isPhoneNumber.py program and does the same thing.
Here, we pass our desired pattern to
re.compile()
and store the result-
ing
Regex
object in
phoneNumRegex
. Then we call
search()
on
phoneNumRegex
and
pass
search()
the string we want to match for during the search. The result
of the search gets stored in the variable
mo
. In this example, we know that
our pattern will be found in the string, so we know that a
Match
object will
be returned. Knowing that
mo
contains a
Match
object and not the null value
None
, we can call
group()
on
mo
to return the match. Writing
mo.group()
inside
our
print()
function call displays the whole match,
415-555-4242
.
