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 = /(.*)(Afronding)([0-9\"\.\s:]*)(,\n)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(.*)(Afronding)([0-9\\"\\.\\s:]*)(,\\n)', 'gm') const str = `{ "ImsManifestIdentifier": "MMANIFEST-2b0b0b9e-6a3c-4af6-ac18-903355ffab58", "PackageGuid": "ab8b5d84-b165-4806-a5fc-58d00ce2a195", "PackageVersie": 223296366, "ToetsGuid": "09f5836d-285a-4970-ad93-fb9610201e15", "ToetsVersie": 10001, "RuweScore": "0", "Vaardigheid": "0", "Afronding": "1", "SchoolTypes": { "VOVMBO": "1", "MBO2": "1", "MBO3": "1" } }, { "ImsManifestIdentifier": "MMANIFEST-2b0b0b9e-6a3c-4af6-ac18-903355ffab58", "PackageGuid": "ab8b5d84-b165-4806-a5fc-58d00ce2a195", "PackageVersie": 223296366, "ToetsGuid": "09f5836d-285a-4970-ad93-fb9610201e15", "ToetsVersie": 10001, "RuweScore": "1", "Vaardigheid": "14,0", "Afronding": "1", "SchoolTypes": { "VOVMBO": "1,1", "MBO2": "1,1", "MBO3": "1" } }, { "ImsManifestIdentifier": "MMANIFEST-2b0b0b9e-6a3c-4af6-ac18-903355ffab58", "PackageGuid": "ab8b5d84-b165-4806-a5fc-58d00ce2a195", "PackageVersie": 223296366, "ToetsGuid": "09f5836d-285a-4970-ad93-fb9610201e15", "ToetsVersie": 10001, "RuweScore": "2", "Vaardigheid": "23", "Afronding": "1", "SchoolTypes": { "VOVMBO": "2,5", "MBO2": "2,5", "MBO3": "1,5" } }`; // 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