Regular Expressions 101

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/
^((https?|ftp):\/\/([a-z0-9_\x{00a1}-\x{ffff}]+([a-z0-9\-:@\x{00a1}-\x{ffff}]*[a-z0-9\x{00a1}-\x{ffff}]+)?([\.\-_][a-z0-9\x{00a1}-\x{ffff}]+)+)(\/[0-9a-z\-_.$%()\x{00a1}-\x{ffff}]*)*(:\d*)?\/?([?|#]([\w\d=_\-$&%.])*)*)$
/
gm
^ asserts position at start of a line
1st Capturing Group
((https?|ftp):\/\/([a-z0-9_\x{00a1}-\x{ffff}]+([a-z0-9\-:@\x{00a1}-\x{ffff}]*[a-z0-9\x{00a1}-\x{ffff}]+)?([\.\-_][a-z0-9\x{00a1}-\x{ffff}]+)+)(\/[0-9a-z\-_.$%()\x{00a1}-\x{ffff}]*)*(:\d*)?\/?([?|#]([\w\d=_\-$&%.])*)*)
2nd Capturing Group
(https?|ftp)
1st Alternative
https?
http
matches the characters http literally (case sensitive)
s
matches the character s with index 11510 (7316 or 1638) literally (case sensitive)
2nd Alternative
ftp
ftp
matches the characters ftp literally (case sensitive)
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
3rd Capturing Group
([a-z0-9_\x{00a1}-\x{ffff}]+([a-z0-9\-:@\x{00a1}-\x{ffff}]*[a-z0-9\x{00a1}-\x{ffff}]+)?([\.\-_][a-z0-9\x{00a1}-\x{ffff}]+)+)
Match a single character present in the list below
[a-z0-9_\x{00a1}-\x{ffff}]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
\x{00a1}-\x{ffff} matches a single character in the range between ¡ (index 161) and ￿ (index 65535) (case sensitive)
4th Capturing Group
([a-z0-9\-:@\x{00a1}-\x{ffff}]*[a-z0-9\x{00a1}-\x{ffff}]+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[a-z0-9\-:@\x{00a1}-\x{ffff}]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
:@
matches a single character in the list :@ (case sensitive)
\x{00a1}-\x{ffff} matches a single character in the range between ¡ (index 161) and ￿ (index 65535) (case sensitive)
Match a single character present in the list below
[a-z0-9\x{00a1}-\x{ffff}]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\x{00a1}-\x{ffff} matches a single character in the range between ¡ (index 161) and ￿ (index 65535) (case sensitive)
5th Capturing Group
([\.\-_][a-z0-9\x{00a1}-\x{ffff}]+)+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character present in the list below
[\.\-_]
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
_ matches the character _ with index 9510 (5F16 or 1378) literally (case sensitive)
Match a single character present in the list below
[a-z0-9\x{00a1}-\x{ffff}]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
\x{00a1}-\x{ffff} matches a single character in the range between ¡ (index 161) and ￿ (index 65535) (case sensitive)
6th Capturing Group
(\/[0-9a-z\-_.$%()\x{00a1}-\x{ffff}]*)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Match a single character present in the list below
[0-9a-z\-_.$%()\x{00a1}-\x{ffff}]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
\- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
_.$%()
matches a single character in the list _.$%() (case sensitive)
\x{00a1}-\x{ffff} matches a single character in the range between ¡ (index 161) and ￿ (index 65535) (case sensitive)
7th Capturing Group
(:\d*)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\/
matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
8th Capturing Group
([?|#]([\w\d=_\-$&%.])*)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character present in the list below
[?|#]
?|#
matches a single character in the list ?|# (case sensitive)
9th Capturing Group
([\w\d=_\-$&%.])*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
Match a single character present in the list below
[\w\d=_\-$&%.]
\w matches any word character (equivalent to [a-zA-Z0-9_])
\d matches a digit (equivalent to [0-9])
=_
matches a single character in the list =_ (case sensitive)
\- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
$&%.
matches a single character in the list $&%. (case sensitive)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String