Python RegEx不匹配，但regexr.com具有相同的表达式

Question

I'm trying to use the following code to match the text est/(?P[0-9]{4}).

using: https://regexr.com/

it matches the text, however in python it fails to match the same text with the same expression:

[^a-z0-9\/]

Here is the code with both conditions. I'm not sure why the regEx will match in regexr.com but not in python unless there is a number sign.

import os
import re

#no work
if re.match("[^a-z0-9\/]", "test/(?P<year>[0-9]{4})"):
    print "match"
else:
    print "no match"

#works
if re.match("[^a-z0-9\/]", "#test/(?P<year>[0-9]{4})"):
    print "match"
else:
    print "no match"

Answer 1

In your first code snippet:

if re.match("[^a-z0-9\/]", "test/(?P<year>[0-9]{4})"):
    print "match"
else:
    print "no match"

The pattern [^a-z0-9\\/] is being applied starting at the beginning of the text. Hence, it fails because the first letter is t , which does not match the pattern. If you intend to just match a single character corresponding to your original pattern, then you may try the following pattern:

.*[^a-z0-9\/].*

This pattern will match for both of your example strings. If you intend to use another pattern, then edit your question and give us more logic.