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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<label\b.*?(data-html=""NewItem"").*?>.*?<\/label>"; string input = @"<div class=""pagination"" data-source=""jsonfields""><!-- Top bar content goes here --><div class=""control""><label class=""btn-process jsNewItem"" data-html=""NewItem"" data-action=""createitem""><span class=""navlink-icon""><i class=""bx bx-list-plus""></i></span></label><label class=""btn-process jsPageItem active pagelink"" data-html=""PageItem"" data-index=""1"" data-action=""navipage""><span class=""navlink-text "">1</span><!-- <span class=""></span> --><!-- <input type=""hidden"" class=""text-input "" data-parent="" name="" data-suffix="" value=""> --></label><label class=""btn-process jsPageItem false pagelink"" data-html=""PageItem"" data-index=""2"" data-action=""navipage""><span class=""navlink-text "">2</span><!-- <span class=""></span> --><!-- <input type=""hidden"" class=""text-input "" data-parent="" name="" data-suffix="" value=""> --></label></div><div class=""parameters""><label class=""btn-process checkbox jsAutoItem pagelink"" data-action=""autorefresh""><input type=""checkbox"" class=""text-input jsAutoRefresh"" data-parent=""{$CLASSPARENT_FIELDS}"" name=""autorefresh"" {$AUTOREFRESH_FIELD}> Autorefresh</label><label class=""btn-process jsRefreshPage pagelink"" data-action=""refreshpage""><span class=""navlink-icon""><i class=""bx bx-refresh""></i></span></label></div></div> <div class=""pagination"" data-source=""jsonfields""><!-- Top bar content goes here --><div class=""control""><label class=""btn-process jsNewItem"" data-html=""NewItem"" data-action=""createitem""><span class=""navlink-icon""><i class=""bx bx-list-plus""></i></span></label><label class=""btn-process jsPageItem active pagelink"" data-html=""PageItem"" data-index=""1"" data-action=""navipage""><span class=""navlink-text "">1</span><!-- <span class=""></span> --><!-- <input type=""hidden"" class=""text-input "" data-parent="" name="" data-suffix="" value=""> --></label><label class=""btn-process jsPageItem false pagelink"" data-html=""PageItem"" data-index=""2"" data-action=""navipage""><span class=""navlink-text "">2</span><!-- <span class=""></span> --><!-- <input type=""hidden"" class=""text-input "" data-parent="" name="" data-suffix="" value=""> --></label></div><div class=""parameters""><label class=""btn-process checkbox jsAutoItem pagelink"" data-action=""autorefresh""><input type=""checkbox"" class=""text-input jsAutoRefresh"" data-parent=""{$CLASSPARENT_FIELDS}"" name=""autorefresh"" {$AUTOREFRESH_FIELD}> Autorefresh</label><label class=""btn-process jsRefreshPage pagelink"" data-action=""refreshpage""><span class=""navlink-icon""><i class=""bx bx-refresh""></i></span></label></div></div>"; foreach (Match m in Regex.Matches(input, pattern)) { 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