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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /(?:^(?:[^|]*\|){7}\s)?([^=]+)=((?:\\\\=|[^=])+)(?:\s|$)/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:^(?:[^|]*\\|){7}\\s)?([^=]+)=((?:\\\\\\\\=|[^=])+)(?:\\s|$)', 'g') const str = `eventId=621 externalId=7B48F50417A7455B9A2C1596B3C35AD3 start=1396040742441 end=1396040742443 catdt=Network-based IDS/IPS art=1396041080694 deviceSeverity=10 rt=1396041064361 dhost=ILOD-7VWN4M1 dst=10.20.103.36 destinationZoneURI=/All Zones/ArcSight System/Private Address Space Zones/RFC1918: 10.0.0.0-10.255.255.255 duser=Sim809 dproc=C:/Program Files (x86)/Microsoft Office/Office14/WINWORD.EXE filePath=E:/PARA 304 Pre-Trial Litigation/~WRD2772.tmp fsize=0 cs1=Log files written to USB drives | Log writing to USB drives flexString1=Site PRDMWWVSEPCON01 flexString2=Behavior cs1Label=Rule Name flexString1Label=Sep Site flexString2Label=Table ahost=prdjcapauacol02.associateaux.local agt=10.127.161.121 agentZoneURI=/All Zones/ArcSight System/Private Address Space Zones/RFC1918: 10.0.0.0-10.255.255.255 av=6.0.6.6865.0 atz=America/New_York aid=3gE+HCkUBABDhUsTXWORqkQ\\\\=\\\\= at=flexmulti_db dtz=America/New_York _cefVer=0.1 ad.USN.l=24433421 ad.GROUP__ID.c=D25FA45B0A6C6585003891A1914F817E ad.ACTION__TYPE.i=0 ad.SEND__SNMP__TRAP.i=0 ad.SITE__ID.c=2E3D68EF0A75961000FEAE1DA37518DA ad.EVENT__TIME.l=1396040806566 ad.ALERT.l=0 ad.PARAM__DEVICE__ID=USBSTOR\\\\\\\\Disk&Ven_Generic&Prod_Flash_Disk&Rev_8.07\\\\\\\\D6CC8E8A&0 ad.HARDWARE__KEY.c=E0B36DF9F91D7648753022D74006E1D1 ad.SERVER__ID.c=480FA3CE0A759610009ADF490BB8CBF3 ad.COMPUTER__ID.c=A7F4EE620A86644B00793AD899D78878 ad.CALLER__PROCESS__ID.l=28612 ad.AGENT__ID.c=7FF540280A86644B00793AD85F2B4CAB ad.ACTION.l=3 ad.DOMAIN__ID.c=C03FE8790A86644B00BA689B2F82C09B ad.VAPI__NAME=File Write `; // 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