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

const regex = /^.*\bgetHouseName:\h+(.+)(?:\R(?!.*price).*)*\R.*price\h+\(in doll\)\h+\[min:\h+(\d+),\h+max:\h+(\d+)\](?:\R(?!.*squaremtr).*)*\R.*squaremtr\h+\(in doll\)\h+\[min: (\d+),\h+max:(\d+)\](?:\R(?!.*sellVal).*)*\R.*sellVal\h+\(in doll\)\h+\[min:\h+(\d+),\h+max:\h+(\d+)\](?:\R(?!.*rentPrice).*)*\R.*rentPrice\(in doll\)\h+\[min: (\d+),\h+max:\h+(\d+)\] /gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^.*\\bgetHouseName:\\h+(.+)(?:\\R(?!.*price).*)*\\R.*price\\h+\\(in doll\\)\\h+\\[min:\\h+(\\d+),\\h+max:\\h+(\\d+)\\](?:\\R(?!.*squaremtr).*)*\\R.*squaremtr\\h+\\(in doll\\)\\h+\\[min: (\\d+),\\h+max:(\\d+)\\](?:\\R(?!.*sellVal).*)*\\R.*sellVal\\h+\\(in doll\\)\\h+\\[min:\\h+(\\d+),\\h+max:\\h+(\\d+)\\](?:\\R(?!.*rentPrice).*)*\\R.*rentPrice\\(in doll\\)\\h+\\[min: (\\d+),\\h+max:\\h+(\\d+)\\] ', 'gm') const str = `[04:04:04s] [startedRetrieving]getHouseName: house1 [04:04:04s] [startedRetrieving]random useless text [04:04:04s] [startedRetrieving]price (in doll) [min: 1000, max: 1200] [04:04:05s] [startedRetrieving]squaremtr (in doll) [min: 75, max:85] [04:04:04s] [startedRetrieving]sellVal (in doll) [min: 1000, max: 1200] [04:04:05s] [startedRetrieving]random useless text [04:04:05s] [startedRetrieving]random useless text [04:04:05s] [startedRetrieving]random useless text [04:04:05s] [startedRetrieving]rentPrice(in doll) [min: 150, max: 200] [04:06:04s] [startedRetrieving]getHouseName: house2 [04:06:04s] [startedRetrieving]price(in doll) [min: 1004, max 1100] [04:06:04s] [startedRetrieving]squaremtr(in doll) [min: 85, max 99] [04:06:04s] [startedRetrieving]sellVal(in doll) [min: 950, max: 1050] [04:06:04s] [startedRetrieving]random useless text [04:06:04s] [startedRetrieving]rentPrice(in doll) [min: 150, max: 290] [04:09:04s] [startedRetrieving]getHouseName: house3 [04:09:04s] [startedRetrieving]price(in doll) [min: 1099, max: 1200] [04:09:04s] [startedRetrieving]squaremtr(in doll) [min: 90, max: 110] [04:09:04s] [startedRetrieving]random useless text [04:09:04s] [startedRetrieving]random useless text [04:09:04s] [startedRetrieving]sellVal(in doll) [min: 1100, max: 1300] [04:09:04s] [startedRetrieving]random useless text [04:09:04s] [startedRetrieving]rentPrice(in doll) [min: 199, max: 300]`; // 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