Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8

Function

  • Match
  • Substitution
  • List
  • Unit Tests
/
\?((?:(?<rid>regionId)=(?<ridv>[\d\$,_]+)|(?<sid>sectionId)=(?<sidv>(?P>ridv))|(?<a>age)=(?<av>(?P>ridv))|(?<p>purpose)=(?<pv>(?P>ridv))|(?<l>lineId)=(?<lv>(?P>ridv))|(?<stid>stationId)=(?<stidv>(?P>ridv))|(?<pe>price)=(?<pev>(?P>ridv)))&?)+
/
m
\? matches the character ? with index 6310 (3F16 or 778) literally (case sensitive)
1st Capturing Group
((?:(?<rid>regionId)=(?<ridv>[\d\$,_]+)|(?<sid>sectionId)=(?<sidv>(?P>ridv))|(?<a>age)=(?<av>(?P>ridv))|(?<p>purpose)=(?<pv>(?P>ridv))|(?<l>lineId)=(?<lv>(?P>ridv))|(?<stid>stationId)=(?<stidv>(?P>ridv))|(?<pe>price)=(?<pev>(?P>ridv)))&?)+
+ 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
Non-capturing group
(?:(?<rid>regionId)=(?<ridv>[\d\$,_]+)|(?<sid>sectionId)=(?<sidv>(?P>ridv))|(?<a>age)=(?<av>(?P>ridv))|(?<p>purpose)=(?<pv>(?P>ridv))|(?<l>lineId)=(?<lv>(?P>ridv))|(?<stid>stationId)=(?<stidv>(?P>ridv))|(?<pe>price)=(?<pev>(?P>ridv)))
1st Alternative
(?<rid>regionId)=(?<ridv>[\d\$,_]+)
Named Capture Group rid
(?<rid>regionId)
regionId
matches the characters regionId literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group ridv
(?<ridv>[\d\$,_]+)
Match a single character present in the list below
[\d\$,_]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\d matches a digit (equivalent to [0-9])
\$ matches the character $ with index 3610 (2416 or 448) literally (case sensitive)
,_
matches a single character in the list ,_ (case sensitive)
2nd Alternative
(?<sid>sectionId)=(?<sidv>(?P>ridv))
Named Capture Group sid
(?<sid>sectionId)
sectionId
matches the characters sectionId literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group sidv
(?<sidv>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
3rd Alternative
(?<a>age)=(?<av>(?P>ridv))
Named Capture Group a
(?<a>age)
age
matches the characters age literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group av
(?<av>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
4th Alternative
(?<p>purpose)=(?<pv>(?P>ridv))
Named Capture Group p
(?<p>purpose)
purpose
matches the characters purpose literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group pv
(?<pv>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
5th Alternative
(?<l>lineId)=(?<lv>(?P>ridv))
Named Capture Group l
(?<l>lineId)
lineId
matches the characters lineId literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group lv
(?<lv>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
6th Alternative
(?<stid>stationId)=(?<stidv>(?P>ridv))
Named Capture Group stid
(?<stid>stationId)
stationId
matches the characters stationId literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group stidv
(?<stidv>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
7th Alternative
(?<pe>price)=(?<pev>(?P>ridv))
Named Capture Group pe
(?<pe>price)
price
matches the characters price literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group pev
(?<pev>(?P>ridv))
(?P>ridv) recurses the subpattern named ridv
&
matches the character & with index 3810 (2616 or 468) literally (case sensitive)
Global pattern flags
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

/
/
m

Test String

Code Generator

Generated Code

Loading code sample...
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php