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"
"

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(\{(?:.|\n)*\})"; string input = @"// API callback google.search.Search.apiary2387({ ""cursor"": { ""currentPageIndex"": 0, ""estimatedResultCount"": ""4490"", ""moreResultsUrl"": ""http://www.google.com/cse?oe=utf8&ie=utf8&source=uds&q=ssh&start=0&sort=&cx=013305635491195529773:0ufpuq-fpt0"", ""resultCount"": ""4,490"", ""searchResultTime"": ""0.22"", ""pages"": [ { ""label"": 1, ""start"": ""0"" }, { ""label"": 2, ""start"": ""1"" }, { ""label"": 3, ""start"": ""2"" }, { ""label"": 4, ""start"": ""3"" }, { ""label"": 5, ""start"": ""4"" }, { ""label"": 6, ""start"": ""5"" }, { ""label"": 7, ""start"": ""6"" }, { ""label"": 8, ""start"": ""7"" }, { ""label"": 9, ""start"": ""8"" }, { ""label"": 10, ""start"": ""9"" } ] }, ""context"": { ""title"": ""Pastebin Active"", ""total_results"": ""0"", ""facets"": [] }, ""results"": [ { ""GsearchResultClass"": ""GwebSearch"", ""cacheUrl"": ""http://www.google.com/search?q=cache:PBL2A25kpZoJ:pastebin.com"", ""clicktrackUrl"": ""https://www.google.com/url?q=http://pastebin.com/u/ssh&sa=U&ved=0ahUKEwiO4fjNpovMAhWBPxoKHYJXAS4QFggEMAA&client=internal-uds-cse&usg=AFQjCNHczEhDXdcUnRZhpArEeSiHfjwMJA"", ""content"": ""BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\n. SIGN UP takes 10 seconds, and it&#39;s free! Guest&nbsp;..."", ""contentNoFormatting"": ""BitBucket - Backup your code in the cloud! Host unlimited private projects, for free\n. SIGN UP takes 10 seconds, and it's free! Guest ..."", ""formattedUrl"": ""pastebin.com/u/\u003cb\u003essh\u003c/b\u003e"", ""title"": ""\u003cb\u003eSsh&#39;s\u003c/b\u003e Pastebin - Pastebin.com"", ""titleNoFormatting"": ""Ssh's Pastebin - Pastebin.com"", ""unescapedUrl"": ""http://pastebin.com/u/ssh"", ""url"": ""http://pastebin.com/u/ssh"", ""visibleUrl"": ""pastebin.com"", ""richSnippet"": { ""cseImage"": { ""src"": ""http://pastebin.com/i/facebook.png"" }, ""metatags"": { ""fbAppId"": ""231493360234820"", ""ogTitle"": ""Ssh's Pastebin - Pastebin.com"", ""ogType"": ""article"", ""ogUrl"": ""http://pastebin.com/u/ssh"", ""ogImage"": ""http://pastebin.com/i/facebook.png"", ""ogSiteName"": ""Pastebin"", ""viewport"": ""width=device-width, maximum-scale=1.0, user-scalable=no"" } } } ] } );"; Match m = Regex.Match(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