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

const regex = /[\r\n]+\[\d{4}-\d{2}-\d{2}\s+\d{2}:\d{2}:\d{2}\.\d+-\d{2}:\d{2}\|info]\*[^\r\n]+([\r\n]+)\[\d{4}-\d{2}-\d{2}\s+\d{2}:\d{2}:\d{2}\.\d+-\d{2}:\d{2}\|info\]Line/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('[\\r\\n]+\\[\\d{4}-\\d{2}-\\d{2}\\s+\\d{2}:\\d{2}:\\d{2}\\.\\d+-\\d{2}:\\d{2}\\|info]\\*[^\\r\\n]+([\\r\\n]+)\\[\\d{4}-\\d{2}-\\d{2}\\s+\\d{2}:\\d{2}:\\d{2}\\.\\d+-\\d{2}:\\d{2}\\|info\\]Line', 'gm') const str = `[2019-12-18 07:00:01.070924-07:00|info]Line 3: :begin [2019-12-18 07:00:01.070924-07:00|info]Line 4: [2019-12-18 07:00:01.070924-07:00|info]Line 5: WORKINGDIR "C:\\Download\\Server1" [2019-12-18 07:00:01.070924-07:00|info]*Working directory: C:\\Download\\Server1\\ [2019-12-18 07:00:01.070924-07:00|info]Line 6: [2019-12-18 07:00:01.070924-07:00|info]Line 7: FTPLOGON "Server1" /timeout=60 [2019-12-18 07:00:01.070924-07:00|info]*Logging on to <server1> as SFTP (SSH File Transfer Protocol) [2019-12-18 07:00:01.070924-07:00|info]*Logon in progress... [2019-12-18 07:00:03.055523-07:00|info]*Logon successful. [2019-12-18 07:00:03.055523-07:00|info]Line 8: FTPCD "Extracts" [2019-12-18 07:00:03.164909-07:00|info]*Current FTP site directory: /Extracts/ [2019-12-18 07:00:03.164909-07:00|info]Line 9: IFERROR= \$ERROR_SUCCESS GOTO Operation1 [2019-12-18 07:00:03.164909-07:00|info]Line 21: :Operation1 [2019-12-18 07:00:03.164909-07:00|info]Line 22: FTPGETFILE "*na_alert_subs*" /newest [2019-12-18 07:00:03.164909-07:00|info]*Hint: FTPGETFILE /newest always returns the newest file [2019-12-18 07:00:03.430561-07:00|info]Line 22: *%sitefile has been set to: na_alert_subs_20191217.txt [2019-12-18 07:00:03.446223-07:00|info]Line 23: RCVFILE %sitefile /delete [2019-12-18 07:00:03.446223-07:00|info]*Receiving to "C:\\Download\\Server1\\na_alert_subs_20191217.txt" [2019-12-18 07:00:12.947244-07:00|info]*Complete, received 1394788 bytes in 9 seconds (1513.44K cps) [2019-12-18 07:00:13.103506-07:00|info]*File deleted on FTP site. [2019-12-18 07:00:13.103506-07:00|info]*Download complete, 1 file received. ​ `; // 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