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 = @"http://www\.myurl\.com/\?action=joingiveaway&amp;id=([0-9]+)"; string input = @" <DIV> <H2><A style=""COLOR: black"" href=""http://www.myurl.com/?action=viewgiveaways&amp;id=287"">New car Giveaway</A></H2></DIV> <DIV style=""MARGIN-TOP: 6px"">The Winner of this giveaway will win a new car!</DIV> <DIV class=box_round style=""BORDER-TOP: red 1px solid; BORDER-RIGHT: red 1px solid; BORDER-BOTTOM: red 1px solid; PADDING-BOTTOM: 8px; PADDING-TOP: 8px; PADDING-LEFT: 8px; BORDER-LEFT: red 1px solid; MARGIN-TOP: 10px; PADDING-RIGHT: 8px""> <DIV><B>Special Requirement : </B></DIV> <DIV style=""MARGIN-TOP: 2px"">You need to have earned atleast <B style=""COLOR: blue"">1000 Coins </B>in total to enter this Giveaway </DIV> <DIV style=""COLOR: green; MARGIN-TOP: 2px"">Your total coin earnings is 21707 </DIV></DIV> <DIV style=""MARGIN-TOP: 6px""><B>Entry Fee : 20 Coins</B></DIV> <DIV style=""MARGIN: 6px""><A class=cssbutton style=""COLOR: white"" href=""http://www.myurl.com/?action=joingiveaway&amp;id=287"">Enter Giveaway</A><BR><SMALL>You have 0 entries</SMALL></DIV></DIV> <DIV style=""FLOAT: right""> <DIV>Group : Everyone</DIV> <DIV>Multiple Entries : No</DIV> <DIV>Total Entries : <A href=""http://www.myurl.com/?action=viewentries&amp;giveawayid=287"">4</A></DIV> <DIV>Max Entries : 100</DIV> <DIV>Start Date : Jan 23 2013</DIV> <DIV><A href=""http://www.myurl.com/index.php?action=faq#coins"" target=_blank>How To Earn Coins?</A></DIV></DIV> <DIV style=""CLEAR: both""></DIV></DIV></DIV></DIV> <DIV class=index-left style=""FLOAT: right; PADDING-TOP: 15px; PADDING-RIGHT: 23px""> <DIV class=left-section> "; 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