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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"""PrivKey"": ""([a-zA-Z0-9_=\/-\\+]+)"; string input = @" { ""API"": { ""HTTPHeaders"": {} }, ""Addresses"": { ""API"": ""/ip4/0.0.0.0/tcp/5001"", ""Announce"": [], ""Gateway"": ""/ip4/0.0.0.0/tcp/8080"", ""NoAnnounce"": [], ""Swarm"": [ ""/ip4/0.0.0.0/tcp/4001"", ""/ip6/::/tcp/4001"" ] }, ""Bootstrap"": [ ""/dnsaddr/bootstrap.libp2p.io/ipfs/QmNnooDu7bfjPFoTZYxMNLWUQJyrVwtbZg5gBMjTezGAJN"", ""/dnsaddr/bootstrap.libp2p.io/ipfs/QmQCU2EcMqAqQPR2i9bChDtGNJchTbq5TbXJJ16u19uLTa"", ""/dnsaddr/bootstrap.libp2p.io/ipfs/QmbLHAnMoJPWSCR5Zhtx6BHJX9KiKNN6tpvbUcqanj75Nb"", ""/dnsaddr/bootstrap.libp2p.io/ipfs/QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt"", ""/ip4/104.131.131.82/tcp/4001/ipfs/QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ"", ""/ip4/104.236.179.241/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM"", ""/ip4/128.199.219.111/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu"", ""/ip4/104.236.76.40/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64"", ""/ip4/178.62.158.247/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd"", ""/ip6/2604:a880:1:20::203:d001/tcp/4001/ipfs/QmSoLPppuBtQSGwKDZT2M73ULpjvfd3aZ6ha4oFGL1KrGM"", ""/ip6/2400:6180:0:d0::151:6001/tcp/4001/ipfs/QmSoLSafTMBsPKadTEgaXctDQVcqN88CNLHXMkTNwMKPnu"", ""/ip6/2604:a880:800:10::4a:5001/tcp/4001/ipfs/QmSoLV4Bbm51jM9C4gDYZQ9Cy3U6aXMJDAbzgu2fzaDs64"", ""/ip6/2a03:b0c0:0:1010::23:1001/tcp/4001/ipfs/QmSoLer265NRgSp2LA3dPaeykiS1J6DifTC88f5uVQKNAd"" ], ""Datastore"": { ""BloomFilterSize"": 1048576, ""GCPeriod"": ""1h"", ""HashOnRead"": false, ""Spec"": { ""child"": { ""path"": ""badgerds"", ""syncWrites"": true, ""truncate"": true, ""type"": ""badgerds"" }, ""prefix"": ""badger.datastore"", ""type"": ""measure"" }, ""StorageGCWatermark"": 90, ""StorageMax"": ""100GB"" }, ""Discovery"": { ""MDNS"": { ""Enabled"": true, ""Interval"": 10 } }, ""Experimental"": { ""FilestoreEnabled"": false, ""Libp2pStreamMounting"": false, ""P2pHttpProxy"": false, ""PreferTLS"": false, ""QUIC"": false, ""ShardingEnabled"": false, ""UrlstoreEnabled"": false }, ""Gateway"": { ""APICommands"": [], ""HTTPHeaders"": { ""Access-Control-Allow-Headers"": [ ""X-Requested-With"", ""Range"", ""User-Agent"" ], ""Access-Control-Allow-Methods"": [ ""GET"" ], ""Access-Control-Allow-Origin"": [ ""*"" ] }, ""NoFetch"": false, ""PathPrefixes"": [], ""RootRedirect"": "", ""Writable"": false }, ""Identity"": { ""PeerID"": ""Qme2joV44qiG38Q7YaEti6N1QMiM6XujXairxgJqJB9DeT"", ""PrivKey"": ""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"" }, ""Ipns"": { ""RecordLifetime"": "", ""RepublishPeriod"": "", ""ResolveCacheSize"": 128 }, ""Mounts"": { ""FuseAllowOther"": false, ""IPFS"": ""/ipfs"", ""IPNS"": ""/ipns"" }, ""Pubsub"": { ""DisableSigning"": false, ""Router"": "", ""StrictSignatureVerification"": false }, ""Reprovider"": { ""Interval"": ""12h"", ""Strategy"": ""all"" }, ""Routing"": { ""Type"": ""dht"" }, ""Swarm"": { ""AddrFilters"": null, ""ConnMgr"": { ""GracePeriod"": ""20s"", ""HighWater"": 2000, ""LowWater"": 600, ""Type"": ""basic"" }, ""DisableBandwidthMetrics"": false, ""DisableNatPortMap"": false, ""DisableRelay"": false, ""EnableAutoNATService"": false, ""EnableAutoRelay"": false, ""EnableRelayHop"": false } }"; 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