Regular Expressions 101

Save & Share

  • Regex Version: ver. 2
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

`
`
sg

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @" *<hashTree>. *<JSONPathAssertion.*?</JSONPathAssertion>. *<hashTree/>. *</hashTree>."; string input = @"<?xml version=""1.0"" encoding=""UTF-8""?> <jmeterTestPlan version=""1.2"" properties=""5.0"" jmeter=""5.1.1 r1855137""> <hashTree> <TestPlan guiclass=""TestPlanGui"" testclass=""TestPlan"" testname=""test one"" enabled=""true""> <stringProp name=""TestPlan.comments""></stringProp> <boolProp name=""TestPlan.functional_mode"">false</boolProp> <boolProp name=""TestPlan.tearDown_on_shutdown"">true</boolProp> <boolProp name=""TestPlan.serialize_threadgroups"">false</boolProp> <elementProp name=""TestPlan.user_defined_variables"" elementType=""Arguments"" guiclass=""ArgumentsPanel"" testclass=""Arguments"" testname=""User Defined Variables"" enabled=""true""> <collectionProp name=""Arguments.arguments""/> </elementProp> <stringProp name=""TestPlan.user_define_classpath""></stringProp> </TestPlan> <hashTree> <com.blazemeter.jmeter.threads.concurrency.ConcurrencyThreadGroup guiclass=""com.blazemeter.jmeter.threads.concurrency.ConcurrencyThreadGroupGui"" testclass=""com.blazemeter.jmeter.threads.concurrency.ConcurrencyThreadGroup"" testname=""Thread - main"" enabled=""true""> <elementProp name=""ThreadGroup.main_controller"" elementType=""com.blazemeter.jmeter.control.VirtualUserController""/> <stringProp name=""ThreadGroup.on_sample_error"">continue</stringProp> <stringProp name=""TargetLevel"">${__P(threads, 1)}</stringProp> <stringProp name=""RampUp"">${__P(time, 1)}</stringProp> <stringProp name=""Steps"">${__P(steps, 1)}</stringProp> <stringProp name=""Hold"">${__P(hold, 3)}</stringProp> <stringProp name=""LogFilename""></stringProp> <stringProp name=""Iterations""></stringProp> <stringProp name=""Unit"">M</stringProp> </com.blazemeter.jmeter.threads.concurrency.ConcurrencyThreadGroup> <hashTree> <GenericController guiclass=""LogicControllerGui"" testclass=""GenericController"" testname=""Simple Controller - main"" enabled=""true""/> <hashTree> <HTTPSamplerProxy guiclass=""HttpTestSampleGui"" testclass=""HTTPSamplerProxy"" testname=""REQUEST1"" enabled=""true""> <boolProp name=""HTTPSampler.postBodyRaw"">true</boolProp> <elementProp name=""HTTPsampler.Arguments"" elementType=""Arguments""> <collectionProp name=""Arguments.arguments""> <elementProp name="" elementType=""HTTPArgument""> <boolProp name=""HTTPArgument.always_encode"">false</boolProp> <stringProp name=""Argument.value"">{&#xd; &quot;version&quot;: &quot;1.1&quot;,&#xd; &quot;test&quot;: {&#xd; }</stringProp> <stringProp name=""Argument.metadata"">=</stringProp> </elementProp> </collectionProp> </elementProp> <stringProp name=""HTTPSampler.domain""></stringProp> <stringProp name=""HTTPSampler.port""></stringProp> <stringProp name=""HTTPSampler.protocol""></stringProp> <stringProp name=""HTTPSampler.contentEncoding""></stringProp> <stringProp name=""HTTPSampler.path""></stringProp> <stringProp name=""HTTPSampler.method"">POST</stringProp> <boolProp name=""HTTPSampler.follow_redirects"">false</boolProp> <boolProp name=""HTTPSampler.auto_redirects"">false</boolProp> <boolProp name=""HTTPSampler.use_keepalive"">true</boolProp> <boolProp name=""HTTPSampler.DO_MULTIPART_POST"">false</boolProp> <stringProp name=""HTTPSampler.embedded_url_re""></stringProp> <stringProp name=""HTTPSampler.connect_timeout""></stringProp> <stringProp name=""HTTPSampler.response_timeout""></stringProp> </HTTPSamplerProxy> <hashTree> <JSONPathAssertion guiclass=""JSONPathAssertionGui"" testclass=""JSONPathAssertion"" testname=""JSON Assertion"" enabled=""true""> <stringProp name=""JSON_PATH"">$.status</stringProp> <stringProp name=""EXPECTED_VALUE"">ok</stringProp> <boolProp name=""JSONVALIDATION"">true</boolProp> <boolProp name=""EXPECT_NULL"">false</boolProp> <boolProp name=""INVERT"">false</boolProp> <boolProp name=""ISREGEX"">false</boolProp> </JSONPathAssertion> <hashTree/> <JSR223PreProcessor guiclass=""TestBeanGUI"" testclass=""JSR223PreProcessor"" testname=""JSR223 PreProcessor"" enabled=""true""> <stringProp name=""cacheKey"">true</stringProp> <stringProp name=""filename""></stringProp> <stringProp name=""parameters""></stringProp> <stringProp name=""script"">// period in the past - year-month-day, set from properties in User Defined Variables import java.time.Instant; import java.time.temporal.ChronoUnit; import groovy.json.JsonOutput; import org.apache.commons.lang.RandomStringUtils;</stringProp> <stringProp name=""scriptLanguage"">groovy</stringProp> </JSR223PreProcessor> <hashTree/> <JSR223PostProcessor guiclass=""TestBeanGUI"" testclass=""JSR223PostProcessor"" testname=""JSR223 PostProcessor"" enabled=""true""> <stringProp name=""cacheKey"">true</stringProp> <stringProp name=""filename""></stringProp> <stringProp name=""parameters""></stringProp> <stringProp name=""script"">import java.time.Instant; import java.time.temporal.ChronoUnit;</stringProp> <stringProp name=""scriptLanguage"">groovy</stringProp> </JSR223PostProcessor> <hashTree/> </hashTree> <IfController guiclass=""IfControllerPanel"" testclass=""IfController"" testname=""If Controller"" enabled=""true""> <stringProp name=""IfController.condition"">${__groovy(${random_variable} == 1)}</stringProp> <boolProp name=""IfController.evaluateAll"">false</boolProp> <boolProp name=""IfController.useExpression"">true</boolProp> </IfController> <hashTree> <RandomController guiclass=""RandomControlGui"" testclass=""RandomController"" testname=""Random Controller"" enabled=""true""> <intProp name=""InterleaveControl.style"">1</intProp> </RandomController> <hashTree> <HTTPSamplerProxy guiclass=""HttpTestSampleGui"" testclass=""HTTPSamplerProxy"" testname=""REQUEST2"" enabled=""true""> <boolProp name=""HTTPSampler.postBodyRaw"">true</boolProp> <elementProp name=""HTTPsampler.Arguments"" elementType=""Arguments""> <collectionProp name=""Arguments.arguments""> <elementProp name="" elementType=""HTTPArgument""> <boolProp name=""HTTPArgument.always_encode"">false</boolProp> <stringProp name=""Argument.value"">{&#xd; &quot;version&quot;: &quot;1.1&quot;,&#xd; &quot;test&quot;: {&#xd; }</stringProp> <stringProp name=""Argument.metadata"">=</stringProp> </elementProp> </collectionProp> </elementProp> <stringProp name=""HTTPSampler.domain""></stringProp> <stringProp name=""HTTPSampler.port""></stringProp> <stringProp name=""HTTPSampler.protocol""></stringProp> <stringProp name=""HTTPSampler.contentEncoding""></stringProp> <stringProp name=""HTTPSampler.path""></stringProp> <stringProp name=""HTTPSampler.method"">POST</stringProp> <boolProp name=""HTTPSampler.follow_redirects"">false</boolProp> <boolProp name=""HTTPSampler.auto_redirects"">false</boolProp> <boolProp name=""HTTPSampler.use_keepalive"">true</boolProp> <boolProp name=""HTTPSampler.DO_MULTIPART_POST"">false</boolProp> <stringProp name=""HTTPSampler.embedded_url_re""></stringProp> <stringProp name=""HTTPSampler.connect_timeout""></stringProp> <stringProp name=""HTTPSampler.response_timeout""></stringProp> </HTTPSamplerProxy> <hashTree> <JSONPathAssertion guiclass=""JSONPathAssertionGui"" testclass=""JSONPathAssertion"" testname=""JSON Assertion"" enabled=""true""> <stringProp name=""JSON_PATH"">$.status</stringProp> <stringProp name=""EXPECTED_VALUE"">ok</stringProp> <boolProp name=""JSONVALIDATION"">true</boolProp> <boolProp name=""EXPECT_NULL"">false</boolProp> <boolProp name=""INVERT"">false</boolProp> <boolProp name=""ISREGEX"">false</boolProp> </JSONPathAssertion> <hashTree/> </hashTree> </hashTree> </hashTree> </hashTree> </hashTree> </hashTree> </hashTree> </jmeterTestPlan>"; RegexOptions options = RegexOptions.Singleline; 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