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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"File size.*?<span[^>]*>(\d+\.?\d*\s*[KMG]B)<\/span>"; string input = @"<div id=""morpheusDesktopCelwidget"" class=""a-section a-spacing-none celwidget""><div id=""bfae-desktop-main-content"" class=""a-section a-spacing-large celwidget sidesheetWidget""><div id=""morpheus-header"" class=""a-row _bW9yc_header-sticky_3psnt""><div id=""morpheus-header-title"" class=""a-section a-spacing-none""><div class=""a-row _bW9yc_title-row_1ABR4 _bW9yc_sticky-header-title_3xWoM"" dir=""auto""><div class=""a-column a-span6 _bW9yc_title-column_11SVA""><h1 id=""morpheus-heading-title"" class=""a-size-base a-text-bold"" dir=""auto"">5 formats &amp; editions</h1></div><div class=""a-column a-span6 a-text-right _bW9yc_title-column_11SVA a-span-last""><span class=""a-declarative"" data-action=""a-popover"" data-csa-c-type=""widget"" data-csa-c-func-deps=""aui-da-a-popover"" data-a-popover=""{&quot;position&quot;:&quot;triggerBottom&quot;,&quot;inlineContent&quot;:&quot;Results are primarily sorted by price&quot;,&quot;closeButton&quot;:&quot;true&quot;}""><a href=""javascript:void(0)"" role=""button"" class=""a-popover-trigger a-declarative"">How are results ordered?<i class=""a-icon a-icon-popover""></i></a></span></div></div></div><hr aria-hidden=""true"" class=""a-spacing-none a-divider-normal _bW9yc_custom-divider_2qkyu""/><div id=""morpheus-header-formats"" class=""a-section a-spacing-none""><div class=""a-section a-spacing-base a-spacing-top-base _bW9yc_formats-scroller_2YNW7""><tags-scroller id=""formats"" tags=""[{&quot;name&quot;:&quot;Kindle (1)&quot;,&quot;selected&quot;:true,&quot;id&quot;:&quot;kindle_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B07P1QTM2P/book-formats-and-editions?selectedFormats=%5B%22kindle_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Audiobook (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;audiobooks_digital_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B07QFSM4RJ/book-formats-and-editions?selectedFormats=%5B%22audiobooks_digital_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Hardcover (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;hardcover_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/1945051639/book-formats-and-editions?selectedFormats=%5B%22hardcover_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Paperback (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;paperback_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/1945051825/book-formats-and-editions?selectedFormats=%5B%22paperback_meta_binding%22%5D&quot;},{&quot;name&quot;:&quot;Spiral-bound (1)&quot;,&quot;selected&quot;:false,&quot;id&quot;:&quot;spiral_bound_meta_binding&quot;,&quot;reference&quot;:&quot;/api/marketplaces/ATVPDKIKX0DER/products/B08GHD27JR/book-formats-and-editions?selectedFormats=%5B%22spiral_bound_meta_binding%22%5D&quot;}]"" data-mix-operations=""formatPillClickHandler"" selectionmode=""single""><input type=""hidden"" name="" value=""/api/marketplaces/ATVPDKIKX0DER/products/B07P1QTM2P/book-formats-and-editions?selectedFormats=%5B%22kindle_meta_binding%22%5D"" id=""kindle_meta_binding-formatReference""/><input type=""hidden"" name="" value=""/api/marketplaces/ATVPDKIKX0DER/products/B07QFSM4RJ/book-formats-and-editions?selectedFormats=%5B%22audiobooks_digital_meta_binding%22%5D"" id=""audiobooks_digital_meta_binding-formatReference""/><input type=""hidden"" name="" value=""/api/marketplaces/ATVPDKIKX0DER/products/1945051639/book-formats-and-editions?selectedFormats=%5B%22hardcover_meta_binding%22%5D"" id=""hardcover_meta_binding-formatReference""/><input type=""hidden"" name="" value=""/api/marketplaces/ATVPDKIKX0DER/products/1945051825/book-formats-and-editions?selectedFormats=%5B%22paperback_meta_binding%22%5D"" id=""paperback_meta_binding-formatReference""/><input type=""hidden"" name="" value=""/api/marketplaces/ATVPDKIKX0DER/products/B08GHD27JR/book-formats-and-editions?selectedFormats=%5B%22spiral_bound_meta_binding%22%5D"" id=""spiral_bound_meta_binding-formatReference""/></tags-scroller></div><hr aria-hidden=""true"" class=""a-spacing-none a-divider-normal""/></div></div><div id=""kindle_meta_binding"" class=""a-row _bW9yc_pill-content_2rpOw""><div class=""sidesheetAsinListContainer"" id=""morpheus-asin-list""><div class=""a-section editions-container""><div class=""_bW9yc_item_138i_""><div class=""a-section a-spacing-none _bW9yc_edition-item_1KJ__""><input type=""hidden"" value=""B07P1QTM2P"" aria-hidden=""true""/><div class=""a-row _bW9yc_asin-upper-section_1r6w9""><div class=""a-column a-span2""><div data-mix-operations=""editionClickHandler""><a aria-hidden=""true"" aria-label=""Starting a Business QuickStart Guide: The Simplified Beginner’s Guide to Launching a Successful Small Business, Turning Your Vision into Reality, and Achieving ... (Starting a Business - QuickStart Guides)"" class=""a-size-mini a-spacing-mini a-spacing-top-micro a-link-normal _bW9yc_img-link_3-kr7"" tabindex=""-1"" href=""/Starting-Business-QuickStart-Guide-Entrepreneurial-ebook/dp/B07P1QTM2P/ref=monarch_sidesheet_image""><img alt="" src=""https://m.media-amazon.com/images/I/71e3axVLfNL._AC_.jpg"" aria-hidden=""true"" class=""_bW9yc_cover_22Xe6""/></a></div></div><div class=""a-column a-span10 a-span-last""><div data-mix-operations=""editionClickHandler""><h2 id=""asinItemTitleB07P1QTM2P"" class=""a-size-base a-text-bold""><a class=""a-spacing-mini a-spacing-top-micro a-link-normal _bW9yc_link_1JCGH"" href=""/Starting-Business-QuickStart-Guide-Entrepreneurial-ebook/dp/B07P1QTM2P/ref=monarch_sidesheet_title"">Starting a Business QuickStart Guide: The Simplified Beginner’s Guide to Launching a Successful Small Business, Turning Your Vision into Reality, and Achieving ... (Starting a Business - QuickStart Guides)</a></h2></div></div><div class=""a-column a-span10 a-span-last""><div class=""a-section a-spacing-top-small _bW9yc_offer-section_3KU5H""><div class=""a-section a-spacing-none _bW9yc_price-section_1ormK""><span class=""a-price"" data-a-size=""xl"" data-a-color=""base""><span class=""a-offscreen"">$15.49</span><span aria-hidden=""true""><span class=""a-price-symbol"">$</span><span class=""a-price-whole"">15<span class=""a-price-decimal"">.</span></span><span class=""a-price-fraction"">49</span></span></span></div></div></div></div><hr aria-hidden=""true"" class=""a-spacing-medium a-spacing-top-small a-divider-normal""/><div class=""a-section""><div class=""a-row""><dl class=""a-definition-list a-vertical _bW9yc_metadata-sec_1pdTz"" role=""presentation""><div class=""a-column a-span12 a-spacing-none""><div class=""a-row""><div class=""a-column a-span6 a-spacing-none""><dt class=""a-list-item""><span class=""a-size-small"">Edition</span></dt></div><div class=""a-column a-span6 a-spacing-none a-span-last""><dd class=""a-list-item""><span class=""a-size-small"">1</span></dd></div></div></div><div class=""a-column a-span12 a-spacing-none""><div class=""a-row""><div class=""a-column a-span6 a-spacing-none""><dt class=""a-list-item""><span class=""a-size-small"">Print length</span></dt></div><div class=""a-column a-span6 a-spacing-none a-span-last""><dd class=""a-list-item""><span class=""a-size-small"">434 pages</span></dd></div></div></div><div class=""a-column a-span12 a-spacing-none""><div class=""a-row""><div class=""a-column a-span6 a-spacing-none""><dt class=""a-list-item""><span class=""a-size-small"">Publication date</span></dt></div><div class=""a-column a-span6 a-spacing-none a-span-last""><dd class=""a-list-item""><span class=""a-size-small"">February 24, 2019</span></dd></div></div></div><div class=""a-column a-span12 a-spacing-none""><div class=""a-row""><div class=""a-column a-span6 a-spacing-none""><dt class=""a-list-item""><span class=""a-size-small"">File size</span></dt></div><div class=""a-column a-span6 a-spacing-none a-span-last""><dd class=""a-list-item""><span class=""a-size-small"">4.3 MB</span></dd></div></div></div></dl></div></div></div><hr aria-hidden=""true"" class=""a-divider-normal _bW9yc_divider_3EwUq""/></div></div><div class=""a-section a-spacing-none kindle_meta_binding_pagination_container""></div></div></div><div id=""audiobooks_digital_meta_binding"" class=""a-row _bW9yc_pill-content_2rpOw""></div><div id=""hardcover_meta_binding"" class=""a-row _bW9yc_pill-content_2rpOw""></div><div id=""paperback_meta_binding"" class=""a-row _bW9yc_pill-content_2rpOw""></div><div id=""spiral_bound_meta_binding"" class=""a-row _bW9yc_pill-content_2rpOw""></div></div></div> "; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx