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

@
@
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = ' <ProjectReference Include="..\\..\\Project1\\Project1\\Project1.csproj"> <Project>{714c6b26-c609-40a4-80a9-421bd842562d}</Project> <Name>Project1</Name> </ProjectReference> <ItemGroup> <ProjectReference Include="..\\..\\Project2\\Project2.csproj"> <Project>{6c2a7631-8b47-4ae9-a68f-f728666105b9}</Project> <Name>Project2</Name> </ProjectReference> <ProjectReference Include="..\\..\\Project3\\Project3\\Project3.csproj"> <Project>{39860208-8146-429f-a1d1-5f8ed2fd7f5f}</Project> <Name>Project3</Name> </ProjectReference> <ProjectReference Include="..\\..\\Project4\\Project4.csproj"> <Project>{58144d60-19d9-4d11-8ae6-088e03ccf874}</Project> <Name>Project4</Name> </ProjectReference> <ProjectReference Include="..\\..\\Project5\\Project5.csproj"> <Project>{33baa509-ad24-4a72-a2fc-8f297e75e90d}</Project> <Name>Project5</Name> </ProjectReference> </ItemGroup> <PropertyGroup> <VisualStudioVersion Condition="\'$(VisualStudioVersion)\' == \'\'">10.0</VisualStudioVersion> <VSToolsPath Condition="\'$(VSToolsPath)\' == \'\'">$(MSBuildExtensionsPath32)\\Microsoft\\VisualStudio\\v$(VisualStudioVersion)</VSToolsPath> </PropertyGroup>'; my $regex = qr@(<ProjectReference.*?Project2[\s\S]*?</ProjectReference>)@mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html