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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'Microsoft ADFS logs and here is an example: 05/07/2019 03:06:54 PM LogName=Security SourceName=AD FS Auditing EventCode=411 EventType=0 Type=Information ComputerName=x.y.z User=abc Sid=A-9-3-98-1231231313-1231231313-1231231313-406293 SidType=1 TaskCategory=Printers OpCode=Info RecordNumber=###### Keywords=Audit Failure, Classic Message=Token validation failed. See inner exception for more details. Additional Data Activity ID: 00000000-0000-0000-0000-000000000000 Token Type: http://schemas.microsoft.com/ws/2006/05/identitymodel/tokens/UserName Client IP: 10.1.1.1,10.1.1.2 Error message: user@foo.com -The user name or password is incorrect Exception details: System.IdentityModel.Tokens.SecurityTokenValidationException: user@foo.com ---> System.ComponentModel.Win32Exception: The user name or password is incorrect at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserHandle(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, SafeCloseHandle& tokenHandle, SafeLsaReturnBufferHandle& profileHandle) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserInfo(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String authenticationType, String issuerName) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUser(UserNameSecurityToken token, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String issuerName) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token) --- End of inner exception stack trace --- at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateToken(SecurityToken token) System.ComponentModel.Win32Exception (0x80004005): The user name or password is incorrect at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserHandle(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, SafeCloseHandle& tokenHandle, SafeLsaReturnBufferHandle& profileHandle) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUserInfo(SafeHGlobalHandle pLogonInfo, Int32 logonInfoSize, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String authenticationType, String issuerName) at Microsoft.IdentityServer.Service.Tokens.LsaLogonUserHelper.GetLsaLogonUser(UserNameSecurityToken token, DateTime& nextPasswordChange, DateTime& lastPasswordChange, String issuerName) at Microsoft.IdentityServer.Service.Tokens.MSISWindowsUserNameSecurityTokenHandler.ValidateTokenInternal(SecurityToken token)'; my $regex = qr/(Token\sType):\s+\S+ Client IP: (?<adfs_src>(?:\d{1,3}\.){3}\d{1,3}(?:,(?:\d{1,3}\.){3}\d{1,3})*)/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