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

/
/
gi

Test String

Code Generator

Generated Code

const regex = /#(\d+)\s*=\s*([a-zA-Z0-9]+)\s*\((.*\s*\S*)\);/gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('#(\\d+)\\s*=\\s*([a-zA-Z0-9]+)\\s*\\((.*\\s*\\S*)\\);', 'gi') const str = `#1=IFCOWNERHISTORY(#89024,#44585,\$,.NOCHANGE.,\$,\$,\$,1190720890); #2=IFCSPACE('3YQLb9Ev54MBIbtTd8JFin',#1,'0001',\$,\$,#88513,#78663,'DesignGross_Floor_2',.ELEMENT.,.INTERNAL.,\$); #3=IFCSLAB('2DGdC704bA7vMD4RPklWqS',#1,'S01','',\$,#28410,#77505,\$,.FLOOR.); #4=IFCCONNECTIONSURFACEGEOMETRY(#83383,\$); #5=IFCCONNECTIONSURFACEGEOMETRY(#84374,\$); #6=IFCGEOMETRICREPRESENTATIONCONTEXT('Plan','Model',3,1.0E-5,#17,#18276); #7=IFCGEOMETRICREPRESENTATIONCONTEXT('Plan','Design',3,1.0E-5,#17,#18276); #8=IFCCARTESIANPOINT((0.0,0.0,0.0)); #9=IFCDIRECTION((0.0,0.0,1.0)); #10=IFCDIRECTION((1.0,0.0,0.0)); #11=IFCCARTESIANPOINT((0.0,0.0)); #12=IFCDIRECTION((0.0,1.0,0.0)); #13=IFCMATERIAL('Column A'); #14=IFCEXTRUDEDAREASOLID(#28326,#17,#9,3657.6); #15=IFCCARTESIANPOINT((0.0,3048.0,0.0)); #16=IFCLOCALPLACEMENT(#4428,#17); #17=IFCAXIS2PLACEMENT3D(#8,#9,#10); #18=IFCPROPERTYSINGLEVALUE('IsExterior',\$,IFCBOOLEAN(.T.),\$); #19=IFCDIRECTION((-1.0,0.0,0.0)); #20=IFCDIRECTION((0.0,-1.0,0.0)); `; // 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