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

r"
"
g

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(above|below|title|data[0-9]*|header[0-9]*|caption|above|label[0-9]*) *= +([^{}|\\n]+)[^| \\n]', 'g') const str = `{{Infobox |name = {{subst:PAGENAME}} |bodystyle = |titlestyle = |abovestyle = background:#cfc; |subheaderstyle = |title = Test Infobox |above = Above text |subheader = Subheader above image |subheader2 = Second subheader |imagestyle = |captionstyle = | image = [[File:example.png|200px|alt=Example alt text]] |caption = Caption displayed below example.png |headerstyle = background:#ccf; |labelstyle = background:#ddf; |datastyle = |header1 = Header defined alone | label1 = | data1 = |header2 = | label2 = Label defined alone does not display (needs data, or is suppressed) | data2 = |header3 = | label3 = | data3 = Data defined alone |header4 = All three defined (header, label, data, all with same number) | label4 = does not display (same number as a header) | data4 = does not display (same number as a header) |header5 = | label5 = Label and data defined (label) | data5 = Label and data defined (data) |belowstyle = background:#ddf; |below = Below text }} {{Infobox | title = Top level title | header1 = {{Infobox | decat = yes | child = yes | title = First subsection | label1= Label 1.1 | data1 = Data 1.1 }} | header2 = {{Infobox | decat = yes | child = yes | title = Second subsection | label1= Label 2.1 | data1 = Data 2.1 }} | belowstyle = | below = Below text }} {{Infobox |name = {{subst:PAGENAME}} |bodystyle = width:20em |titlestyle = |title = Test Infobox |headerstyle = |labelstyle = width:33% |datastyle = |header1 = | label1 = Label 1 | data1 = Data 1 |header2 = | label2 = Label 2 | data2 = Data 2 |header3 = | label3 = Label 3 | data3 = Data 3 |header4 = Header 4 | label4 = | data4 = |header5 = | label5 = Label 5 | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. |belowstyle = |below = Below text }} {{Infobox |name = {{subst:PAGENAME}} |bodystyle = width:20em |titlestyle = |title = Test Infobox |headerstyle = |labelstyle = width:33% |datastyle = |header1 = | label1 = Label 1 | data1 = Data 1 |header2 = | label2 = Label 2 | data2 = Data 2 |header3 = | label3 = Label 3 | data3 = Data 3 |header4 = Header 4 | label4 = | data4 = |header5 = | label5 = Label 5 | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. |belowstyle = |below = Below text }} {{Infobox |name = {{subst:PAGENAME}} |bodystyle = width:20em |titlestyle = |title = Test Infobox |headerstyle = |labelstyle = width:33% |datastyle = |header1 = | label1 = Label 1 | data1 = Data 1 |header2 = | label2 = Label 2 | data2 = Data 2 |header3 = | label3 = Label 3 | data3 = Data 3 |header4 = Header 4 | label4 = | data4 = |header5 = | label5 = Label 5 | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. |belowstyle = |below = Below text }} {{Infobox |name = {{subst:PAGENAME}} |bodystyle = width:20em |titlestyle = |title = Test Infobox |headerstyle = |labelstyle = width:33% |datastyle = |header1 = | label1 = Label 1 | data1 = Data 1 |header2 = | label2 = Label 2 | data2 = Data 2 |header3 = | label3 = Label 3 | data3 = Data 3 |header4 = Header 4 | label4 = | data4 = |header5 = | label5 = Label 5 | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. |belowstyle = |below = Below text }} {{Infobox | headerstyle = background-color:#eee; | labelstyle = background-color:#eee; | header1 = Main 1 | header2 = Main 2 | data3 = {{Infobox | subbox = yes | headerstyle = background-color:#ccc; | labelstyle = background-color:#ddd; | header1 = Sub 3-1 | header2 = Sub 3-2 | label3 = Label 3-3 | data3 = Data 3-3 }} | data4 = {{Infobox | subbox = yes | labelstyle = background-color:#ccc; | label1 = Label 4-1 | data1 = Data 4-1 }} | label5 = Label 5 | data5 = Data 5 | header6 = Main 6 }} {{Infobox | headerstyle = background-color:#eee; | labelstyle = background-color:#eee; | header1 = Main 1 | header2 = Main 2 | data3 = {{Infobox | subbox = yes | headerstyle = background-color:#ccc; | labelstyle = background-color:#ddd; | header1 = Sub 3-1 | header2 = Sub 3-2 | label3 = Label 3-3 | data3 = Data 3-3 }} | data4 = {{Infobox | subbox = yes | labelstyle = background-color:#ccc; | label1 = Label 4-1 | data1 = Data 4-1 }} | label5 = Label 5 | data5 = Data 5 | header6 = Main 6 }} `; // 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