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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gmi

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(?<date>\d{4}-\d{2}-\d{2})\s*(?<time>\d{2}:\d{2}:\d{2}:\d{3})\s*\[\s*(?<level>\w*)\s*(?<module>.*?)\s*\]\s*(?<message>.*)$"; string input = @"2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(""path"", ""chunk"", ""transferid"", ""errorcount"", ""size"", ""modtime"", ""contentChecksum"") 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec ""PRAGMA table_info('conflicts');"" 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(""path"", ""baseFileId"", ""baseEtag"", ""baseModtime"", ""basePath"") 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec ""CREATE INDEX IF NOT EXISTS metadata_e2e_id ON metadata(e2eMangledName);"" 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: Last exec affected 0 rows. 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::commitInternal ]: Transaction commit ""update database structure: add e2eMangledName index"" and starting new transaction 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec ""PRAGMA table_info('blacklist');"" 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::tableColumns ]: Columns in the current journal: QVector(""path"", ""lastTryEtag"", ""lastTryModtime"", ""retrycount"", ""errorstring"", ""lastTryTime"", ""ignoreDuration"", ""renameTarget"", ""errorCategory"", ""requestId"") 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec ""CREATE INDEX IF NOT EXISTS blacklist_index ON blacklist(path collate nocase);"" 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: Last exec affected 0 rows. 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database ] [ OCC::SyncJournalDb::commitInternal ]: Transaction commit ""checkConnect End"" 2021-09-27 09:28:25:778 [ debug nextcloud.sync.database.sql ] [ OCC::SqlQuery::exec ]: SQL exec ""SELECT COUNT(*) FROM metadata"" 2021-09-27 09:28:25:794 [ info nextcloud.gui.folder.manager ]: Adding folder to Folder Map OCC::Folder(0x2677fdf3ee0) ""1"" 2021-09-27 09:28:25:795 [ info nextcloud.gui.folder.manager ]: Schedule folder ""1"" to sync! 2021-09-27 09:28:25:795 [ info nextcloud.gui.folder.manager ]: Folder is not ready to sync, not scheduled! 2021-09-27 09:28:25:797 [ info nextcloud.gui.application ]: Sync state changed for folder "" : ""Not yet Started"" 2021-09-27 09:28:25:797 [ info nextcloud.sync.clientproxy ]: Set proxy configuration to use the preferred system proxy for http tcp connections 2021-09-27 09:28:25:801 [ debug nextcloud.gui.updater ] [ OCC::Updater::create ]: QUrl(""https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true"") 2021-09-27 09:28:26:533 [ info nextcloud.sync.credentials.webflow ]: Fetch from keychain! 2021-09-27 09:28:26:536 [ info nextcloud.gui.folder.navigationpane ]: Explorer Cloud storage provider: saving path "" to CLSID ""{5cefc208-e391-444c-af93-61c636da9853}"" 2021-09-27 09:28:26:537 [ info nextcloud.gui.socketapi ]: New connection QLocalSocket(0x267027e4570) 2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read ""Nextcloud_clientCertificatePEM:0"" chunk ""0"" ""Password entry not found"" 2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read ""Nextcloud_clientKeyPEM"" chunk ""0"" ""Password entry not found"" 2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.webflow ]: Unable to read client key ""Password entry not found"" 2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.keychainchunk ]: Unable to read ""Nextcloud_su_mssrv01_clientCaCertificatePEM0"" chunk ""0"" ""Password entry not found"" 2021-09-27 09:28:26:538 [ warning nextcloud.sync.credentials.webflow ]: Unable to read client CA cert slot ""0"" ""Password entry not found"" 2021-09-27 09:28:26:538 [ debug nextcloud.sync.account ] [ OCC::Account::slotCredentialsFetched ]: User id already fetched. 2021-09-27 09:28:26:539 [ info nextcloud.gui.account.state ]: Fetched credentials for "" attempting to connect 2021-09-27 09:28:26:539 [ debug nextcloud.sync.account ] [ OCC::Account::resetNetworkAccessManager ]: Resetting QNAM 2021-09-27 09:28:26:539 [ info nextcloud.sync.credentials.webflow ]: Get QNAM 2021-09-27 09:28:26:539 [ debug nextcloud.sync.connectionvalidator ] [ OCC::ConnectionValidator::checkServerAndAuth ]: Checking server and authentication 2021-09-27 09:28:26:539 [ debug nextcloud.sync.connectionvalidator ] [ OCC::ConnectionValidator::checkServerAndAuth ]: Trying to look up system proxy 2021-09-27 09:28:26:540 [ info nextcloud.sync.connectionvalidator ]: No system proxy set by OS 2021-09-27 09:28:26:541 [ info nextcloud.sync.accessmanager ]: 2 "" "" has X-Request-ID ""75765e8e-2b52-4dd9-b67b-62b450feafdc"" 2021-09-27 09:28:26:541 [ debug nextcloud.sync.cookiejar ] [ OCC::CookieJar::cookiesForUrl ]: QUrl("") requests: (QNetworkCookie(""nc_sameSiteCookielax=true; secure; HttpOnly; expires=Fri, 31-Dec-2100 23:59:59 GMT), QNetworkCookie(""nc_sameSiteCookiestrict=true; secure; HttpOnly; expires=Fri, 31-Dec-2100 23:59:59 GMT)) 2021-09-27 09:28:26:541 [ info nextcloud.sync.networkjob ]: OCC::CheckServerJob created for "" + ""status.php"" ""OCC::ConnectionValidator"" 2021-09-27 09:28:26:795 [ debug nextcloud.gui.folderwatcher ] [ OCC::FolderWatcher::pathIsIgnored ]: * Ignoring file ""D:/Shared/NextcloudMirror/.owncloudsync.log"" 2021-09-27 09:28:28:826 [ info nextcloud.gui.updater ]: Checking for available update 2021-09-27 09:28:28:826 [ info nextcloud.sync.accessmanager ]: 2 "" ""https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true"" has X-Request-ID ""2fbd3d8d-a4e6-486f-b0f7-dbd441225cd3"" 2021-09-27 09:28:28:826 [ debug nextcloud.sync.cookiejar ] [ OCC::CookieJar::cookiesForUrl ]: QUrl(""https://updates.nextcloud.org/client/?version=3.3.4.20210920&platform=win32&osRelease=windows&osVersion=server2016&kernelVersion=10.0.17763&oem=Nextcloud&buildArch=x86_64&currentArch=x86_64&versionsuffix=stable-Win64&updatesegment=43&msi=true"") requests: () 2021-09-27 09:28:29:638 [ info nextcloud.sync.credentials.webflow ]: request finished"; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase; 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