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 = /\"Id\":"(\d+)","LocalTime":"(\d+)"/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\"Id\\":"(\\d+)","LocalTime":"(\\d+)"', 'gm') const str = `2020-06-05 01:00:33.919 INFO [Thread-261246][HClient.java:256] - post successefully 2020-06-05 01:00:33.920 INFO [Thread-261246][HClient.java:257] - {"ResponseStatusListObject":{"ResponseStatusObject":[{"RequestURL":"/VIID/Faces","StatusCode":"0","StatusMessage":"正常","Id":"31010713011328005232","LocalTime":"20200605005843"}]}} 2020-06-05 01:00:33.920 INFO [Thread-261246][PutuoHandle.java:104] - list send end, listSize:6, sendTime:757ms 2020-06-05 01:00:34.160 INFO [Thread-261248][HClient.java:256] - post successefully 2020-06-05 01:00:34.160 INFO [Thread-261248][HClient.java:257] - {"ResponseStatusListObject":{"ResponseStatusObject":[{"RequestURL":"/VIID/Faces","StatusCode":"0","StatusMessage":"正常","Id":"31010712011328005082","LocalTime":"20200605010212"}]}} 2020-06-05 01:00:34.196 INFO [Thread-261247][HClient.java:256] - post successefully 2020-06-05 01:00:34.196 INFO [Thread-261247][HClient.java:257] - {"ResponseStatusListObject":{"ResponseStatusObject":[{"RequestURL":"/VIID/Faces","StatusCode":"0","StatusMessage":"正常","Id":"31010712011328005082","LocalTime":"20200605010240"}]}} 2020-06-05 01:00:34.196 INFO [Thread-261247][PutuoHandle.java:104] - list send end, listSize:5, sendTime:954ms 2020-06-05 01:00:34.323 INFO [Thread-261248][HClient.java:256] - post successefully 2020-06-05 01:00:34.323 INFO [Thread-261248][HClient.java:257] - {"ResponseStatusListObject":{"ResponseStatusObject":[{"RequestURL":"/VIID/Faces","StatusCode":"0","StatusMessage":"正常","Id":"31010713011328005232","LocalTime":"20200605005843"}]}} 2020-06-05 01:00:34.510 INFO [Thread-261248][HClient.java:256] - post successefully 2020-06-05 01:00:34.510 INFO [Thread-261248][HClient.java:257] - {"ResponseStatusListObject":{"ResponseStatusObject":[{"RequestURL":"/VIID/Faces","StatusCode":"0","StatusMessage":"正常","Id":"31010711011328005078","LocalTime":"20200605010240"}]}} 2020-06-05 01:00:34.510 INFO [Thread-261248][PutuoHandle.java:104] - list send end, listSize:5, sendTime:1464ms 2020-06-05 01:00:48.939 INFO [Timer-0][PutuoHandleThread.java:29] - area=>PT_AREA cameraType=>HK_TP groupCount=>3 2020-06-05 01:00:48.939 INFO [Timer-0][DbUtil.java:118] - getLastMaxId, cameraType:HK_TP, area:PT_AREA 2020-06-05 01:00:48.940 INFO [Timer-0][DbUtil.java:129] - sql=SELECT maxid FROM t_flag_info WHERE cameraType = ? AND area = ?, 1:HK_TP, 2:PT_AREA`; // 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