Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(\sdoi: 10\.\d{1,50}/\S+\..)"; string input = @"Reliability and validity of the French version of the global physical activity questionnaire."",""/pubmed/30356654"",""Rivière F, Widad FZ, Speyer E, Erpelding ML, Escalon H, Vuillemin A."",""J Sport Health Sci. 2018 Jul;7(3):339-345. doi: 10.1016/j.jshs.2016.08.004. Epub 2016 Aug 15."",""J Sport Health Sci. 2018"",""PubMed"",""citation"",""PMID:30356654 | PMCID:PMC6189276"",""pubmed"",""30356654"",""create date:2018/10/26 | first author:Rivière F jbfkjezfkzjbkzvf doi: 10.3390/pharmaceutics8020011."",""Pharmaceutics. khfkefkzefhzfe doi: 10.18632/oncotarget.8210."",""Oncotarget. jkkgkg doi: 10.3390/molecules21091123."",""Molecules. (3). pii: E27. doi: 10.3390/pharmacy4030027."",""Pharmacy (Basel). 2016"",""PubMed"",""citation"",""PMID:28970400 | PMCID:PMC5419365"",""pubmed"",""28970400"",""create date:2017/10/04 | first author:Atkinson J"", 63(2):175-183. doi: 10.1093/cz/zow048. Epub 2016 Apr 22."",""Curr Zool. 2017"",""PubMed"",""citation"",""PMID:29491975 | PMCID:PMC5804161"",""pubmed"",""29491975"",""create date:2018/03/02 | first author:Colchen T"", 51:209-216. doi: 10.1515/hukin-2015-0184. eCollection 2016 Jun 1."",""J Hum Kinet. 2016"",""PubMed"",""citation"",""PMID:28149384 | PMCID:PMC5260564"",""pubmed"",""28149384"",""create date:2017/02/06 | first author:Rouis M"", 11(12):e0168349. doi: 10.1371/journal.pone.0168349. eCollection 2016."",""PLoS One. 2016"",""PubMed"",""citation"",""PMID:28036335 | PMCID:PMC5201304"",""pubmed"",""28036335"",""create date:2016/12/31 | first author:Huttin O"", 14(9):1124-1137. doi: 10.1080/15476286.2016.1251543. Epub 2016 Oct 28. Review."",""RNA Biol. 2017"",""PubMed"",""citation"",""PMID:27791472 | PMCID:PMC5699547"",""pubmed"",""27791472"",""create date:2016/10/30 | first author:Schwartz S"", 66(1):39-47. doi: 10.1016/j.jhep.2016.08.021. Epub 2016 Sep 10."",""J Hepatol. 2017"",""PubMed"",""citation"",""PMID:27622858"",""pubmed"",""27622858"",""create date:2016/09/14 | first author:Pol S"","; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx