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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(^|[\s:#])0(?!0{7})\d{7}([\s:a-zA-Z]|$)"; string input = @"123 234 10 DETECT: 01234561 wordfromlistc OR wordfromlistd 01234562 OR wordfromlista01234563 OR 01234567wordfromlistb DON'T DETECT: 00000000 wordfromlist OR wordfromlist 0000000 OR 00000000wordfromlist OR wordfromlist00000000 OR DON'T DETECT: 01234567- OR -01234567 OR /01234567/, etc 01234567 00000000 00000001 1505848655000-0400 12345678 {""context"":{""client"":{""clientName"":1,""clientVersion"":""2.20170920""}},""events"":[{""eventTimeMs"":1506022852901,""foregroundHeartbeat"":{""firstActivityMs"":""-1"",""clientDocumentNonce"":""LEPgGrs4OSu6AqVj"",""index"":""8"",""lastEventDeltaMs"":""-1"",""trigger"":""FOREGROUND_HEARTBEAT_TRIGGER_ON_FOREGROUND""},""context"":{""lastActivityMs"":""1791003""}},{""eventTimeMs"":1506022855635,""foregroundHeartbeat"":{""firstActivityMs"":""2311"",""clientDocumentNonce"":""LEPgGrs4OSu6AqVj"",""index"":""9"",""lastEventDeltaMs"":""2733"",""trigger"":""FOREGROUND_HEARTBEAT_TRIGGER_ON_BACKGROUND""},""context"":{""lastActivityMs"":""861""}}],""requestTimeMs"":1506022865644} {""context"":{""client"":{""clientName"":1,""clientVersion"":""2.20170920""}},""interactions"":[{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""trackingParams"":""CAEQumkiEwiSrfTIh7fWAhVB9pwKHVSOCQsojh4=""}]},""eventTimeMs"":1506023726765,""lactMs"":316},{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""veType"":23851,""veCounter"":1}]},""eventTimeMs"":1506023728252,""lactMs"":1803},{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""veType"":36925,""veCounter"":2}]},""eventTimeMs"":1506023728253,""lactMs"":1804},{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""veType"":28664,""veCounter"":3}]},""eventTimeMs"":1506023728253,""lactMs"":1804},{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""veType"":28662,""veCounter"":4}]},""eventTimeMs"":1506023728253,""lactMs"":1804},{""attachChild"":{""csn"":""LBnEWZLnFcHs8wTUnKZY"",""parentVisualElement"":{""veType"":3854},""visualElements"":[{""veType"":28656,""veCounter"":5}]},""eventTimeMs"":1506023728253,""lactMs"":1804},{""attachChild"":{""csn"":""MhnEWc2FDdHY8gT7qJigAw"",""parentVisualElement"":{""veType"":3832},""visualElements"":[{""trackingParams"":""CAEQumkiEwiSrfTIh7fWAhVB9pwKHVSOCQsojh4=""}]},""eventTimeMs"":1506023731445,""lactMs"":560}],""requestTimeMs"":1506023732093}"; foreach (Match m in Regex.Matches(input, pattern)) { 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