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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @/ (\[.*\]\(audio-1 .*\))|(\[.*\]\(img-1 .*\))|(\[\]\(video-1 .*\)) /; string input = @"[null,null,null](img-1 'https://cdnapi.ergolab.cn/api/cdn/files/Teams/Picture/1/2670fff8-2119-c821-d2e6-3a04b72ac556/jsjuHxumPt4yKPRtVfR.png') [null,null,null](img-1 'https://cdnapi.ergolab.cn/api/cdn/files/Teams/Picture/0/2670fff8-2119-c821-d2e6-3a04b72ac556/jsjuHxumPt4yLavx4gv.png') [null,null,null](img-1 'https://cdnapi.ergolab.cn/api/cdn/files/MaterialLibrary/Picture/0/3761f21b-3016-dadd-6198-3a0569770f55/jsjuHxukkZDtF879nQB.jpg') [](audio-1 'https://cdnapi.ergolab.cn/api/cdn/files/Teams/Audio/0/2670fff8-2119-c821-d2e6-3a04b72ac556/jsjuHxumPt4zfnkYB6m.ogg') [](audio-1 'https://cdnapi.ergolab.cn/api/cdn/files/MaterialLibrary/Audio/0/44b29ef1-e567-e1a4-49c6-3a0545afd2f4/jsjuHidHpFagk8AbHt7.mp3') [](video-1 'https://cdnapi.ergolab.cn/api/cdn/files/Teams/Video/0/2670fff8-2119-c821-d2e6-3a04b72ac556/jsjuHxumPt4zfnoXzSB.ogg') [](video-1 'https://cdnapi.ergolab.cn/api/cdn/files/MaterialLibrary/Video/0/ac35f3ad-4cbb-da07-e510-39fd24ba71b5/jseEvLjEA4JXbybZQse.mp4')"; 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