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

import Foundation let pattern = #"(^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]*)(?=".*$)"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive]) let testString = ##""" 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 """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(result)

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression