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

/
/
gmi

Test String

Code Generator

Language

Generated Code

const regex = /(^Project\("{[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}}"\)\s*=\s*"[\w\d-.]*"\s*,\s*")\K([\w\d-.\\\s]*)(?=".*$)/gmi; // Alternative syntax using RegExp constructor // const regex = new RegExp('(^Project\\("{[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}}"\\)\\s*=\\s*"[\\w\\d-.]*"\\s*,\\s*")\\K([\\w\\d-.\\\\\\s]*)(?=".*$)', 'gmi') const str = `Microsoft Visual Studio Solution File, Format Version 12.00 # Visual Studio 14 VisualStudioVersion = 14.0.25420.1 MinimumVisualStudioVersion = 10.0.40219.1 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CCH.WFM.UnitTest.Framework", "Source\\Common\\Tests\\Unit Tests\\WFMTestFramework\\CCH.WFM.UnitTest.Framework.csproj", "{044E36A5-189E-45B1-9753-397BC8ACD31A}" EndProject Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CCH.WFM.ServiceTest", "Source\\Common\\Tests\\Unit Tests\\ServiceTest\\CCH.WFM.ServiceTest.csproj", "{94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}" EndProject Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "TestFramework", "..\\test\\TestFramework\\TestFramework.csproj", "{3F56B03C-0883-4705-91BA-0979CAF6E719}" EndProject Global GlobalSection(SolutionConfigurationPlatforms) = preSolution Debug|Any CPU = Debug|Any CPU Release|Any CPU = Release|Any CPU EndGlobalSection GlobalSection(ProjectConfigurationPlatforms) = postSolution {044E36A5-189E-45B1-9753-397BC8ACD31A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU {044E36A5-189E-45B1-9753-397BC8ACD31A}.Debug|Any CPU.Build.0 = Debug|Any CPU {044E36A5-189E-45B1-9753-397BC8ACD31A}.Release|Any CPU.ActiveCfg = Release|Any CPU {044E36A5-189E-45B1-9753-397BC8ACD31A}.Release|Any CPU.Build.0 = Release|Any CPU {94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Debug|Any CPU.ActiveCfg = Debug|Any CPU {94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Debug|Any CPU.Build.0 = Debug|Any CPU {94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Release|Any CPU.ActiveCfg = Release|Any CPU {94E3C16B-DFBA-403A-95F9-37FAB7AB88ED}.Release|Any CPU.Build.0 = Release|Any CPU {3F56B03C-0883-4705-91BA-0979CAF6E719}.Debug|Any CPU.ActiveCfg = Debug|Any CPU {3F56B03C-0883-4705-91BA-0979CAF6E719}.Debug|Any CPU.Build.0 = Debug|Any CPU {3F56B03C-0883-4705-91BA-0979CAF6E719}.Release|Any CPU.ActiveCfg = Release|Any CPU {3F56B03C-0883-4705-91BA-0979CAF6E719}.Release|Any CPU.Build.0 = Release|Any CPU EndGlobalSection GlobalSection(SolutionProperties) = preSolution HideSolutionNode = FALSE EndGlobalSection GlobalSection(TeamFoundationVersionControl) = preSolution SccNumberOfProjects = 4 SccEnterpriseProvider = {4CA58AB2-18FA-4F8D-95D4-32DDF27D184C} SccTeamFoundationServer = https://tfs2013.prosystemfx.com/tfs/nextgen SccLocalPath0 = . SccProjectUniqueName1 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\WFMTestFramework\\\\CCH.WFM.UnitTest.Framework.csproj SccProjectName1 = Source/Common/Tests/Unit\\u0020Tests/WFMTestFramework SccLocalPath1 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\WFMTestFramework SccProjectUniqueName2 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\ServiceTest\\\\CCH.WFM.ServiceTest.csproj SccProjectName2 = Source/Common/Tests/Unit\\u0020Tests/ServiceTest SccLocalPath2 = Source\\\\Common\\\\Tests\\\\Unit\\u0020Tests\\\\ServiceTest SccProjectUniqueName3 = ..\\\\test\\\\TestFramework\\\\TestFramework.csproj SccProjectName3 = ../test/TestFramework SccLocalPath3 = ..\\\\test\\\\TestFramework EndGlobalSection EndGlobal `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions