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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?:(?:\s+<PackageVersion Include="([^"]+)".*)|.*)/m'; $str = '<Project> <!-- Workaround https://github.com/dependabot/dependabot-core/issues/8490 --> <!-- This file gets imported for out-of-tree test runs also where eng/Versions.props isn\'t available --> <Import Project="eng/Versions.props" Condition="\'$(MajorVersion)\' == \'\' and Exists(\'eng/Versions.props\')" /> <PropertyGroup> <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally> <TestcontainersPackageVersion>3.9.0</TestcontainersPackageVersion> </PropertyGroup> <ItemGroup> <!-- AWS SDK for .NET dependencies --> <PackageVersion Include="AWSSDK.CloudFormation" Version="3.7.308.18" /> <PackageVersion Include="AWSSDK.SQS" Version="3.7.301.26" /> <PackageVersion Include="AWSSDK.SimpleNotificationService" Version="3.7.301.61" /> <PackageVersion Include="AWSSDK.Core" Version="3.7.304.23" /> <PackageVersion Include="AWSSDK.Extensions.NETCore.Setup" Version="3.7.301" /> <PackageVersion Include="AWS.Messaging" Version="0.9.1" /> <PackageVersion Include="OpenTelemetry.Instrumentation.AWS" Version="1.1.0-beta.4" /> <PackageVersion Include="OpenTelemetry.Extensions.AWS" Version="1.3.0-beta.1" /> <!-- Azure SDK for .NET dependencies --> <PackageVersion Include="Azure.AI.OpenAI" Version="1.0.0-beta.17" /> <PackageVersion Include="Azure.Data.Tables" Version="12.8.3" /> <PackageVersion Include="Azure.Extensions.AspNetCore.Configuration.Secrets" Version="1.3.1" /> <PackageVersion Include="Azure.Identity" Version="1.12.0" /> <PackageVersion Include="Azure.Messaging.EventHubs.Processor" Version="5.11.3" /> <PackageVersion Include="Azure.Messaging.ServiceBus" Version="7.17.5" /> <PackageVersion Include="Azure.Search.Documents" Version="11.5.1" /> <PackageVersion Include="Azure.Messaging.WebPubSub" Version="1.3.0" /> <PackageVersion Include="Azure.Security.KeyVault.Secrets" Version="4.6.0" /> <PackageVersion Include="Azure.Storage.Blobs" Version="12.20.0" /> <PackageVersion Include="Azure.Storage.Queues" Version="12.18.0" /> <PackageVersion Include="Microsoft.Azure.AppConfiguration.AspNetCore" Version="7.2.0" /> <PackageVersion Include="Microsoft.Azure.Cosmos" Version="3.41.0" /> <PackageVersion Include="Microsoft.Azure.SignalR" Version="1.25.2" /> <PackageVersion Include="Microsoft.Extensions.Azure" Version="1.7.4" /> <!-- Azure Management SDK for .NET dependencies --> <PackageVersion Include="Azure.Provisioning" Version="0.3.0" /> <PackageVersion Include="Azure.Provisioning.AppConfiguration" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.ApplicationInsights" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.CognitiveServices" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.CosmosDB" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.EventHubs" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.KeyVault" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.OperationalInsights" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.PostgreSql" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.Redis" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.Resources" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.Search" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.ServiceBus" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.SignalR" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.Sql" Version="0.1.0" /> <PackageVersion Include="Azure.Provisioning.Storage" Version="0.2.0" /> <PackageVersion Include="Azure.Provisioning.WebPubSub" Version="0.1.0-beta.1" /> <!-- ASP.NET Core dependencies --> <PackageVersion Include="Microsoft.AspNetCore.Authentication.Certificate" Version="$(MicrosoftAspNetCoreAuthenticationCertificatePackageVersion)" /> <PackageVersion Include="Microsoft.AspNetCore.Authentication.OpenIdConnect" Version="$(MicrosoftAspNetCoreAuthenticationOpenIdConnectPackageVersion)" /> <PackageVersion Include="Microsoft.AspNetCore.OpenApi" Version="$(MicrosoftAspNetCoreOpenApiPackageVersion)" /> <PackageVersion Include="Microsoft.AspNetCore.OutputCaching.StackExchangeRedis" Version="$(MicrosoftAspNetCoreOutputCachingStackExchangeRedisPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Caching.StackExchangeRedis" Version="$(MicrosoftExtensionsCachingStackExchangeRedisPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Diagnostics.HealthChecks.EntityFrameworkCore" Version="$(MicrosoftExtensionsDiagnosticsHealthChecksEntityFrameworkCorePackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Diagnostics.HealthChecks" Version="$(MicrosoftExtensionsDiagnosticsHealthChecksPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Features" Version="$(MicrosoftExtensionsFeaturesPackageVersion)" /> <!-- AspNetCore.HealthChecks dependencies (3rd party packages) --> <PackageVersion Include="AspNetCore.HealthChecks.Azure.Data.Tables" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Azure.KeyVault.Secrets" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Azure.Storage.Blobs" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Azure.Storage.Queues" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.AzureServiceBus" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Kafka" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.MongoDb" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.MySql" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.NpgSql" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Rabbitmq" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.Redis" Version="8.0.1" /> <PackageVersion Include="AspNetCore.HealthChecks.SqlServer" Version="8.0.2" /> <!-- efcore dependencies --> <PackageVersion Include="Microsoft.EntityFrameworkCore.Cosmos" Version="$(MicrosoftEntityFrameworkCoreCosmosPackageVersion)" /> <PackageVersion Include="Microsoft.EntityFrameworkCore.SqlServer" Version="$(MicrosoftEntityFrameworkCoreSqlServerPackageVersion)" /> <PackageVersion Include="Microsoft.EntityFrameworkCore.Tools" Version="$(MicrosoftEntityFrameworkCoreToolsPackageVersion)" /> <PackageVersion Include="Microsoft.EntityFrameworkCore.Design" Version="$(MicrosoftEntityFrameworkCoreDesignPackageVersion)" /> <!-- runtime dependencies--> <PackageVersion Include="Microsoft.Extensions.Configuration.Abstractions" Version="$(MicrosoftExtensionsConfigurationAbstractionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Configuration.Binder" Version="$(MicrosoftExtensionsConfigurationBinderPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="$(MicrosoftExtensionsDependencyInjectionAbstractionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Hosting.Abstractions" Version="$(MicrosoftExtensionsHostingAbstractionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Hosting" Version="$(MicrosoftExtensionsHostingPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Http" Version="$(MicrosoftExtensionsHttpPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Logging.Abstractions" Version="$(MicrosoftExtensionsLoggingAbstractionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Options" Version="$(MicrosoftExtensionsOptionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Primitives" Version="$(MicrosoftExtensionsPrimitivesPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Http.Resilience" Version="$(MicrosoftExtensionsHttpResiliencePackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.TimeProvider.Testing" Version="$(MicrosoftExtensionsTimeProviderTestingVersion)" /> <!-- external dependencies --> <PackageVersion Include="Confluent.Kafka" Version="2.4.0" /> <PackageVersion Include="Dapper" Version="2.1.44" /> <PackageVersion Include="DnsClient" Version="1.8.0" /> <PackageVersion Include="Google.Protobuf" Version="3.27.1" /> <PackageVersion Include="Grpc.AspNetCore" Version="2.63.0" /> <PackageVersion Include="Grpc.Net.ClientFactory" Version="2.63.0" /> <PackageVersion Include="Grpc.Tools" Version="2.64.0" /> <PackageVersion Include="Humanizer.Core" Version="2.14.1" /> <PackageVersion Include="KubernetesClient" Version="14.0.2" /> <PackageVersion Include="Microsoft.Data.SqlClient" Version="5.2.1" /> <PackageVersion Include="Microsoft.FluentUI.AspNetCore.Components" Version="4.7.2" /> <PackageVersion Include="Microsoft.FluentUI.AspNetCore.Components.Icons" Version="4.7.2" /> <PackageVersion Include="Milvus.Client" Version="2.3.0-preview.1"/> <PackageVersion Include="MongoDB.Driver" Version="2.27.0" /> <PackageVersion Include="MongoDB.Driver.Core.Extensions.DiagnosticSources" Version="1.4.0" /> <PackageVersion Include="MySqlConnector.DependencyInjection" Version="2.3.6" /> <PackageVersion Include="MySqlConnector.Logging.Microsoft.Extensions.Logging" Version="2.1.0" /> <PackageVersion Include="NATS.Net" Version="2.3.0" /> <PackageVersion Include="Npgsql.DependencyInjection" Version="8.0.3" /> <PackageVersion Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="8.0.4" /> <PackageVersion Include="Oracle.EntityFrameworkCore" Version="8.23.40" /> <PackageVersion Include="Polly.Core" Version="8.4.1" /> <PackageVersion Include="Polly.Extensions" Version="8.4.1" /> <PackageVersion Include="Pomelo.EntityFrameworkCore.MySql" Version="8.0.2" /> <PackageVersion Include="Qdrant.Client" Version="1.10.0" /> <PackageVersion Include="RabbitMQ.Client" Version="[6.8.1,7.0.0)" /> <PackageVersion Include="StackExchange.Redis" Version="2.8.0" /> <PackageVersion Include="System.IO.Hashing" Version="8.0.0" /> <PackageVersion Include="Yarp.ReverseProxy" Version="2.1.0" /> <!-- Open Telemetry --> <PackageVersion Include="Npgsql.OpenTelemetry" Version="8.0.3" /> <PackageVersion Include="OpenTelemetry.Exporter.InMemory" Version="1.9.0" /> <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.9.0" /> <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.9.0" /> <PackageVersion Include="OpenTelemetry.Instrumentation.GrpcNetClient" Version="1.9.0-beta.1" /> <PackageVersion Include="OpenTelemetry.Instrumentation.Http" Version="1.9.0" /> <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.9.0" /> <PackageVersion Include="OpenTelemetry.Instrumentation.Runtime" Version="1.9.0" /> <!-- build dependencies --> <PackageVersion Include="MicroBuild.Plugins.SwixBuild.Dotnet" Version="1.1.87-gba258badda" /> <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="4.10.0" /> <PackageVersion Include="Microsoft.CodeAnalysis.PublicApiAnalyzers" Version="3.3.4" /> <PackageVersion Include="Microsoft.DotNet.Build.Tasks.Workloads" Version="8.0.0-beta.23564.4" /> <PackageVersion Include="Microsoft.Signed.Wix" Version="$(MicrosoftSignedWixVersion)" /> <PackageVersion Include="Microsoft.DotNet.Build.Tasks.Installers" Version="8.0.0-beta.23564.4" /> <PackageVersion Include="System.CommandLine" Version="2.0.0-beta4.24324.3" /> <!-- unit test dependencies --> <PackageVersion Include="bUnit" Version="1.28.9" /> <PackageVersion Include="JsonSchema.Net" Version="7.1.2" /> <PackageVersion Include="Microsoft.DotNet.RemoteExecutor" Version="$(MicrosoftDotNetRemoteExecutorPackageVersion)" /> <PackageVersion Include="Microsoft.DotNet.XUnitExtensions" Version="$(MicrosoftDotNetXUnitExtensionsPackageVersion)" /> <PackageVersion Include="Microsoft.Extensions.Diagnostics.Testing" Version="$(MicrosoftExtensionsDiagnosticsTestingPackageVersion)" /> <PackageVersion Include="Microsoft.NET.Runtime.WorkloadTesting.Internal" Version="$(MicrosoftNETRuntimeWorkloadTestingInternalVersion)" /> <PackageVersion Include="Microsoft.Playwright" Version="1.45.0" /> <PackageVersion Include="Swashbuckle.AspNetCore" Version="6.6.2" /> <PackageVersion Include="Testcontainers.MongoDb" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.MsSql" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.MySql" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.PostgreSQL" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.RabbitMq" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.Redis" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.Nats" Version="$(TestcontainersPackageVersion)" /> <PackageVersion Include="Testcontainers.Milvus" Version="$(TestcontainersPackageVersion)" /> <!-- playground apps dependencies --> <PackageVersion Include="Dapr.AspNetCore" Version="1.13.1" /> <PackageVersion Include="Microsoft.Orleans.Clustering.AzureStorage" Version="8.2.0" /> <PackageVersion Include="Microsoft.Orleans.Persistence.AzureStorage" Version="8.2.0" /> <PackageVersion Include="Microsoft.Orleans.Client" Version="8.2.0" /> <PackageVersion Include="Microsoft.Orleans.Server" Version="8.2.0" /> <PackageVersion Include="Microsoft.Orleans.Sdk" Version="8.2.0" /> <!-- Pinned version for Component Governance - Remove when root dependencies are updated --> <PackageVersion Include="Newtonsoft.Json" Version="13.0.3" /> </ItemGroup> </Project>'; $subst = "$1,"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php