c# 4.0 - Regex pattern to match groups starting with pattern -

i extract data text stream data structured such

/1-<id>/<rectype>-<data>..repeat n times../1-<id>/#-<data>..repeat n times..  

in above, "/1" field precedes record data can have number of following fields, each choice of rectype 2 9 (also, each field starts "/")

for example:

 /1-xxxx/2-yyyy/9-zzzz/1-aaaa/3-bbbb/5-cccc/8=nnnn/9=dddd/1-qqqq/2-wwww/3=pppp/7-eeee 

so, there 3 groups of data above

 1=xxxx 2=yyyy  9=zzzz  1=aaaa 3=bbbb  5=cccc  8=nnnn  9=dddd  1=qqqq 2=wwww  3=pppp  7=eeee 

data simplicity, know contains [a-z0-9. ] can variable length (not 4 chars per example)

now, following expression sort of works, capturing first 2 fields of each group , none of remaining fields...

/1-(?'fld1'[a-z]+)/((?'fldno'[2-9])-(?'flddata'[a-z0-9\. ]+)) 

i know need sort of quantifier in there somewhere, not know or place it.

you can use regex match these blocks using 2 .net regex features: 1) capture collection , 2) multiple capturing groups same name in pattern. then, we'll need linq magic combine captured data list of lists:

(?<fldno>1)-(?'flddata'[^/]+)(?:/(?<fldno>[2-9])[-=](?'flddata'[^/]+))* 

details:

• (?<fldno>1) - group fldno matching 1
• - - hyphen
• (?'flddata'[^/]+) - group "flddata" capturing 1+ chars other /
• (?:/(?<fldno>[2-9])[-=](?'flddata'[^/]+))* - 0 or more sequences of:
  • / - literal /
  • (?<fldno>[2-9]) - 2 9 digit (group "fldno")
  • [-=] - - or =
  • (?'flddata'[^/]+)- 1+ chars other / (group "flddata")

see regex demo, results:

see c# demo:

using system; using system.linq; using system.text.regularexpressions; public class test {     public static void main()     {         var str = "/1-xxxx/2-yyyy/9-zzzz/1-aaaa/3-bbbb/5-cccc/8=nnnn/9=dddd/1-qqqq/2-wwww/3=pppp/7-eeee";         var res = regex.matches(str, @"(?<fldno>1)-(?'flddata'[^/]+)(?:/(?<fldno>[2-9])[-=](?'flddata'[^/]+))*")             .cast<match>()             .select(p => p.groups["fldno"].captures.cast<capture>().select(m => m.value)                     .zip(p.groups["flddata"].captures.cast<capture>().select(m => m.value),                          (first, second) => first + "=" + second))             .tolist();              foreach (var t in res)                 console.writeline(string.join(" ", t));     } }