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

/
/
gx

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(,\s*(*SKIP))?+ # Attempts to match a comma and advanced whitespaces, # without backtracking; # And if the comma is matched, use (*SKIP) verb, # which advances the pointer if we fail to match the comma. # Key - Value pairs not worthy of keeping. ( ""(?!jobID""|exec)[^""]+"" # Check if we like this key. \s*+:\s*+ # The colon, advance whitespaces. ( # Check keys recursively. ""[^""]*"" # String literals, boring. | {(?2)?+(?>,\s*(?2))*} # Or: An object storing some key-value pairs # we don't care about. | \[(?3)?+(?>,\s*(?3))*\] # Or: An array storing some values # we don't care about. ) ) (?(1)|,?) # Balance the comma (so the result string is still valid JSON)"; string input = @" ""2597401"":[{""jobID"":""2597401"", ""account"":""TG-CCR120014"", ""user"":""charngda"", ""pkgT"":{""pgi/7.2- 5"":{""libA"":[""libpgc.so""], ""flavor"":[""default""]}}, ""startEpoch"":""1338497979"", ""runTime"":""1022"", ""execType"":""user:binary"", ""exec"":""ft.D.64"", ""numNodes"":""4"", ""sha1"":""5a79879235aa31b6a46e73b43879428e2a175db5"", ""execEpoch"":1336766742, ""execModify"":""Fri May 11 15:05:42 2012"", ""startTime"":""Thu May 31 15:59:39 2012"", ""numCores"":""64"", ""sizeT"":{""bss"":""1881400168"",""text"":""239574"",""data"":""22504""}}, {""jobID"":""2597401"", ""account"":""TG-CCR120014"", ""user"":""charngda"", ""pkgT"":{""pgi/7.2-5"":{""libA"":[""libpgc.so""], ""flavor"":[""default""]}}, ""startEpoch"":""1338497946"", ""runTime"":""33"" ""execType"":""user:binary"", ""exec"":""cg.C.64"", ""numNodes"":""4"", ""sha1"":""caf415e011e28b7e4e5b050fb61cbf71a62a9789"", ""execEpoch"":1336766735, ""execModify"":""Fri May 11 15:05:35 2012"", ""startTime"":""Thu May 31 15:59:06 2012"", ""numCores"":""64"", ""sizeT"":{""bss"":""29630984"",""text"":""225749"",""data"":""20360""}}, {""jobID"":""2597401"", ""account"":""TG-CCR120014"", ""user"":""charngda"", ""pkgT"":{""pgi/7.2-5"": {""libA"":[""libpgc.so""], ""flavor"":[""default""]}}, ""startEpoch"":""1338500447"", ""runTime"":""145"", ""execType"":""user:binary"", ""exec"":""mg.D.64"", ""numNodes"":""4"", ""sha1"":""173de32e1514ad097b1c051ec49c4eb240f2001f"", ""execEpoch"":1336766756, ""execModify"":""Fri May 11 15:05:56 2012"", ""startTime"":""Thu May 31 16:40:47 2012"", ""numCores"":""64"", ""sizeT"":{""bss"":""456954120"",""text"":""426186"",""data"":""22184""}},{""jobID"":""2597401"", ""account"":""TG-CCR120014"", ""user"":""charngda"", ""pkgT"":{""pgi/7.2-5"":{""libA"":[""libpgc.so""], ""flavor"":[""default""]}}, ""startEpoch"":""1338499002"", ""runTime"":""1444"", ""execType"":""user:binary"", ""exec"":""lu.D.64"", ""numNodes"":""4"", ""sha1"":""c6dc16d25c2f23d2a3321d4feed16ab7e10c2cc1"", ""execEpoch"":1336766748, ""execModify"":""Fri May 11 15:05:48 2012"", ""startTime"":""Thu May 31 16:16:42 2012"", ""numCores"":""64"", ""sizeT"":{""bss"":""199850984"",""text"":""474218"",""data"":""27064""}}],"; RegexOptions options = RegexOptions.IgnorePatternWhitespace; 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