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

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"""type"":""(?P<threat_purpose>[^:]+):(?P<threat_resource_affected>[^\/]+)\/(?P<threat_name>[^!]+)\!(?P<threat_artifact>[^""]*?)"; string input = @"{""detail-type"":""GuardDuty Finding"",""resources"":[],""source"":""aws.guardduty"",""id"":""xxxxx-xx"",""detail"":{""schemaVersion"":""2.0"",""accountId"":""1234567890"",""region"":""us-west-2"",""partition"":""aws"",""id"":""xxxxxxxx"",""arn"":""arn:aws:guardduty:us-west-2:1234567890:detector/XXXXXXX/finding/xxxxxxx"",""type"":""Trojan:EC2/PhishingDomainRequest!DNS"",""resource"":{""resourceType"":""Instance"",""instanceDetails"":{""instanceId"":""i-99999999"",""instanceType"":""m3.xlarge"",""launchTime"":""2016-08-02T02:05:06Z"",""productCodes"":[{""productCodeId"":""GeneratedFindingProductCodeId"",""productCodeType"":""GeneratedFindingProductCodeType""}],""iamInstanceProfile"":{""arn"":""GeneratedFindingInstanceProfileArn"",""id"":""GeneratedFindingInstanceProfileId""},""networkInterfaces"":[{""ipv6Addresses"":[],""privateDnsName"":""GeneratedFindingPrivateDnsName"",""privateIpAddress"":""127.0.0.1"",""privateIpAddresses"":[{""privateDnsName"":""GeneratedFindingPrivateName"",""privateIpAddress"":""127.0.0.1""}],""subnetId"":""GeneratedFindingSubnetId"",""vpcId"":""ein-ffdd1234"",""securityGroups"":[{""groupName"":""SecurityGroup01"",""groupId"":""GeneratedFindingSecurityId""}],""publicDnsName"":""bbb.com"",""publicIp"":""127.0.0.1""}],""tags"":[{""key"":""GeneratedFindingInstaceTag1"",""value"":""GeneratedFindingInstaceValue1""},{""key"":""ami-99999999"",""imageDescription"":""GeneratedFindingInstaceImageDescription""}],""service"":{""serviceName"":""guardduty"",""detectorId"":""xxxxxx"",""action"":{""actionType"":""DNS_REQUEST"",""dnsRequestAction"":{""domain"":""GeneratedFindingDomainName"",""protocol"":""UDP"",""blocked"":true}},""resourceRole"":""TARGET"",""additionalInfo"":{""threatListName"":""GeneratedFindingThreatListName"",""sample"":true},""eventFirstSeen"":""2020-06-02T20:22:26.350Z"",""eventLastSeen"":""2020-06-03T20:22:26.350Z"",""archived"":false,""count"":1},""severity"":8,""createdAt"":""2020-06-02T20:22:26.350Z"",""updatedAt"":""2020-06-03T20:22:26.350Z"",""title"":""Trojan:EC2/PhishingDomainRequest!DNS"",""description"":""Trojan:EC2/PhishingDomainRequest!DNS""}}},""time"":""2018-02-28T20:25:00Z"",""region"":""us-west-2"",""version"":""0"",""account"":""1234567890""}"; 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