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 = /.*匡威.*\W([0-9a-zA-Z\-]{5,})\W/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('.*匡威.*\\W([0-9a-zA-Z\\-]{5,})\\W', 'gm') const str = `CONVERSE 匡威 男女 CONVERSE ALL STAR系列 Chuck Taylor All Star 休闲鞋 169444C 42码 US8.5码 CONVERSE 匡威 1970S 男女同款 CONVERSE ALL STAR系列 Chuck 70 帆布鞋 167635C 37.5码 US5码 CONVERSE 匡威 1970s 男女 CONVERSE ALL STAR系列 Chuck 70 休闲鞋 170090C 41码 US7.5码 CONVERSE 匡威 男女 配件系列 CAPS 运动 棒球帽 10018890-A10 OSFA码 CONVERSE匡威官方 All Star 男女鞋高帮运动休闲帆布鞋 1Z588 1Z588/黑色 41/7.5 CONVERSE匡威官方 All Star 男女鞋经典款高帮休闲情侣帆布鞋 101010 101010/黑色 35/3 `; // 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