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

/
/

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<date>\[.*?\]) (.*?) ((.|\n*)*)"; string input = @"[2022-07-22 09:53:27,793] INFO KafkaConfig values: advertised.host.name = null advertised.listeners = INTERNAL://0.0.0.0:9092,BROKER://0.0.0.0:9091,CLIENT://0.0.0.0:9093 advertised.port = null alter.config.policy.class.name = null alter.log.dirs.replication.quota.window.num = 11 alter.log.dirs.replication.quota.window.size.seconds = 1 authorizer.class.name = auto.create.topics.enable = true auto.leader.rebalance.enable = true background.threads = 10 broker.id = 0 broker.id.generation.enable = true broker.rack = null client.quota.callback.class = null compression.type = producer connection.failed.authentication.delay.ms = 100 connections.max.idle.ms = 600000 connections.max.reauth.ms = 0 control.plane.listener.name = null controlled.shutdown.enable = true controlled.shutdown.max.retries = 3 controlled.shutdown.retry.backoff.ms = 5000 controller.socket.timeout.ms = 30000 create.topic.policy.class.name = null default.replication.factor = 1 delegation.token.expiry.check.interval.ms = 3600000 delegation.token.expiry.time.ms = 86400000 delegation.token.master.key = null delegation.token.max.lifetime.ms = 604800000 delete.records.purgatory.purge.interval.requests = 1 delete.topic.enable = true fetch.purgatory.purge.interval.requests = 1000 group.initial.rebalance.delay.ms = 3000 group.max.session.timeout.ms = 1800000 group.max.size = 2147483647 group.min.session.timeout.ms = 6000 host.name = inter.broker.listener.name = BROKER inter.broker.protocol.version = 2.3-IV1 kafka.metrics.polling.interval.secs = 10 kafka.metrics.reporters = [] leader.imbalance.check.interval.seconds = 300 leader.imbalance.per.broker.percentage = 10 listener.security.protocol.map = INTERNAL:PLAINTEXT,BROKER:PLAINTEXT,CLIENT:PLAINTEXT listeners = INTERNAL://:9092,BROKER://:9091,CLIENT://:9093 log.cleaner.backoff.ms = 15000 log.cleaner.dedupe.buffer.size = 134217728 log.cleaner.delete.retention.ms = 86400000 log.cleaner.enable = true log.cleaner.io.buffer.load.factor = 0.9 log.cleaner.io.buffer.size = 524288 log.cleaner.io.max.bytes.per.second = 1.7976931348623157E308 log.cleaner.max.compaction.lag.ms = 9223372036854775807 log.cleaner.min.cleanable.ratio = 0.5 log.cleaner.min.compaction.lag.ms = 0 log.cleaner.threads = 1 log.cleanup.policy = [delete] log.dir = /tmp/kafka-logs log.dirs = /var/lib/kafka log.flush.interval.messages = 9223372036854775807 log.flush.interval.ms = null log.flush.offset.checkpoint.interval.ms = 60000 log.flush.scheduler.interval.ms = 9223372036854775807 log.flush.start.offset.checkpoint.interval.ms = 60000 log.index.interval.bytes = 4096 log.index.size.max.bytes = 10485760 log.message.downconversion.enable = true log.message.format.version = 2.3-IV1 log.message.timestamp.difference.max.ms = 9223372036854775807 log.message.timestamp.type = CreateTime log.preallocate = false log.retention.bytes = -1 log.retention.check.interval.ms = 300000 log.retention.hours = 120 log.retention.minutes = null log.retention.ms = null log.roll.hours = 168 log.roll.jitter.hours = 0 log.roll.jitter.ms = null log.roll.ms = null log.segment.bytes = 1073741824 log.segment.delete.delay.ms = 60000 max.connections = 2147483647 max.connections.per.ip = 2147483647 max.connections.per.ip.overrides = max.incremental.fetch.session.cache.slots = 1000 message.max.bytes = 1000012 metric.reporters = [] metrics.num.samples = 2 metrics.recording.level = INFO metrics.sample.window.ms = 30000 min.insync.replicas = 1 num.io.threads = 8 num.network.threads = 3 num.partitions = 1 num.recovery.threads.per.data.dir = 1 num.replica.alter.log.dirs.threads = null num.replica.fetchers = 1 offset.metadata.max.bytes = 4096 offsets.commit.required.acks = -1 offsets.commit.timeout.ms = 5000 offsets.load.buffer.size = 5242880 offsets.retention.check.interval.ms = 600000 offsets.retention.minutes = 10080 offsets.topic.compression.codec = 0 offsets.topic.num.partitions = 50 offsets.topic.replication.factor = 1 offsets.topic.segment.bytes = 104857600 password.encoder.cipher.algorithm = AES/CBC/PKCS5Padding password.encoder.iterations = 4096 password.encoder.key.length = 128 password.encoder.keyfactory.algorithm = null password.encoder.old.secret = null password.encoder.secret = null port = 9092 principal.builder.class = null producer.purgatory.purge.interval.requests = 1000 queued.max.request.bytes = -1 queued.max.requests = 500 quota.consumer.default = 9223372036854775807 quota.producer.default = 9223372036854775807 quota.window.num = 11 quota.window.size.seconds = 1 replica.fetch.backoff.ms = 1000 replica.fetch.max.bytes = 1048576 replica.fetch.min.bytes = 1 replica.fetch.response.max.bytes = 10485760 replica.fetch.wait.max.ms = 500 replica.high.watermark.checkpoint.interval.ms = 5000 replica.lag.time.max.ms = 10000 replica.socket.receive.buffer.bytes = 65536 replica.socket.timeout.ms = 30000 replication.quota.window.num = 11 replication.quota.window.size.seconds = 1 request.timeout.ms = 30000 reserved.broker.max.id = 1000 sasl.client.callback.handler.class = null sasl.enabled.mechanisms = [GSSAPI] sasl.jaas.config = null sasl.kerberos.kinit.cmd = /usr/bin/kinit sasl.kerberos.min.time.before.relogin = 60000 sasl.kerberos.principal.to.local.rules = [DEFAULT] sasl.kerberos.service.name = null sasl.kerberos.ticket.renew.jitter = 0.05 sasl.kerberos.ticket.renew.window.factor = 0.8 sasl.login.callback.handler.class = null sasl.login.class = null sasl.login.refresh.buffer.seconds = 300 sasl.login.refresh.min.period.seconds = 60 sasl.login.refresh.window.factor = 0.8 sasl.login.refresh.window.jitter = 0.05 sasl.mechanism.inter.broker.protocol = GSSAPI sasl.server.callback.handler.class = null security.inter.broker.protocol = PLAINTEXT socket.receive.buffer.bytes = 102400 socket.request.max.bytes = 104857600 socket.send.buffer.bytes = 102400 ssl.cipher.suites = [] ssl.client.auth = none ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1] ssl.endpoint.identification.algorithm = https ssl.key.password = null ssl.keymanager.algorithm = SunX509 ssl.keystore.location = null ssl.keystore.password = null ssl.keystore.type = JKS ssl.principal.mapping.rules = [DEFAULT] ssl.protocol = TLS ssl.provider = null ssl.secure.random.implementation = null ssl.trustmanager.algorithm = PKIX ssl.truststore.location = null ssl.truststore.password = null ssl.truststore.type = JKS transaction.abort.timed.out.transaction.cleanup.interval.ms = 60000 transaction.max.timeout.ms = 900000 transaction.remove.expired.transaction.cleanup.interval.ms = 3600000 transaction.state.log.load.buffer.size = 5242880 transaction.state.log.min.isr = 2 transaction.state.log.num.partitions = 50 transaction.state.log.replication.factor = 3 transaction.state.log.segment.bytes = 104857600 transactional.id.expiration.ms = 604800000 unclean.leader.election.enable = false zookeeper.connect = 0.0.0.0:2181 zookeeper.connection.timeout.ms = 18000 zookeeper.max.in.flight.requests = 10 zookeeper.session.timeout.ms = 6000 zookeeper.set.acl = false zookeeper.sync.time.ms = 2000 (kafka.server.KafkaConfig) [2022-07-22 09:53:27,840] ERROR Fatal error during SupportedServerStartable startup. Prepare to shutdown (io.confluent.support.metrics.SupportedKafka) java.lang.IllegalArgumentException: requirement failed: advertised.listeners cannot use the nonroutable meta-address 0.0.0.0. Use a routable IP address. at scala.Predef$.require(Predef.scala:224) at kafka.server.KafkaConfig.validateValues(KafkaConfig.scala:1492) at kafka.server.KafkaConfig.<init>(KafkaConfig.scala:1460) at kafka.server.KafkaConfig.<init>(KafkaConfig.scala:1114) at kafka.server.KafkaConfig$.fromProps(KafkaConfig.scala:1094) at kafka.server.KafkaConfig$.fromProps(KafkaConfig.scala:1091) at kafka.server.KafkaConfig.fromProps(KafkaConfig.scala) at io.confluent.support.metrics.SupportedServerStartable.<init>(SupportedServerStartable.java:52) at io.confluent.support.metrics.SupportedKafka.main(SupportedKafka.java:45)"; 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