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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\s+# renovate: datasource=(?<datasource>.*?) depName=(?<depName>.*?)( VersionTemplate=(?<VersionTemplate>.*?))?\s+-\s+(?<currentValue>\d+.\d+.\d+).* "; string input = @"--- workflow: rules: - if: $CI_COMMIT_TAG variables: OCI_TAG_FORMAT: ""$CI_COMMIT_TAG"" - when: always variables: OCI_TAG_FORMAT: ""0.0.0-git-$CI_COMMIT_SHORT_SHA"" variables: REPO_URL: ""$CI_REGISTRY_IMAGE"" REPO_IMAGE: $REPO_URL/$DISK_IMAGE_NAME:$OCI_TAG_FORMAT REPO_IMAGE_SNAPSHOT: $REPO_URL/snapshots/$DISK_IMAGE_NAME:$OCI_TAG_FORMAT IMAGE_FORMAT: raw DISK_IMAGE_NAME: $OS-$OS_RELEASE-$FLAVOR-$K8S_FLAVOR GITLEAKS_ARGS: '--verbose --log-opts=$CI_COMMIT_SHA' DIB_SHOW_IMAGE_USAGE: 1 DIB_DEBUG_TRACE: 1 KANOD_OPTIONS_BASE: ""-b no_kanod_network -b lvm -b growpart"" # renovate: datasource=docker UBUNTU_CI_IMAGE: registry.gitlab.com/sylva-projects/sylva-elements/container-images/ci-disk-image-builder/ubuntu:v2.0.8 # renovate: datasource=docker SUSE_CI_IMAGE: registry.gitlab.com/sylva-projects/sylva-elements/container-images/ci-disk-image-builder/suse:v2.0.8 # renovate: datasource=docker GENERATE_OS_SBOM_CI_IMAGE: registry.gitlab.com/sylva-projects/sylva-elements/container-images/trivy-libguestfs:1.0.0 stages: - test - build - release - gitleaks include: - project: 'renovate-bot/renovate-runner' ref: v18.64.1 file: '/templates/renovate-config-validator.gitlab-ci.yml' rules: - if: $CI_PIPELINE_SOURCE == 'merge_request_event' changes: paths: - .gitlab-ci.yml - renovate.json - project: 'sylva-projects/sylva-elements/renovate' ref: 1.0.0 file: '/templates/renovate-dry-run.gitlab-ci.yml' rules: - if: $CI_PIPELINE_SOURCE == 'merge_request_event' changes: paths: - renovate.json - project: ""to-be-continuous/gitleaks"" ref: 2.5.2 file: ""templates/gitlab-ci-gitleaks.yml"" - project: 'sylva-projects/sylva-elements/ci-tooling/ci-templates' ref: 1.0.22 file: - 'templates/release-notes.yml' # Override the release notes suffix to add the images produced during the build .release-notes-after-script: - | apk add curl bash jq curl -sS --header ""PRIVATE-TOKEN: $RELEASE_NOTES_READ_API_TOKEN"" ""${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/pipelines/${CI_PIPELINE_ID}/bridges"" \ | jq "".[].downstream_pipeline.id"" \ | grep -v null \ | xargs -i curl -sS --header ""PRIVATE-TOKEN: $RELEASE_NOTES_READ_API_TOKEN"" ""${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/pipelines/{}/jobs"" \ | jq '.[] | select(.name == ""promote"") | .id' \ | xargs -i curl --location --header ""PRIVATE-TOKEN: $RELEASE_NOTES_READ_API_TOKEN"" --output artifacts-{}.zip ""${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/jobs/{}/artifacts"" ls for z in *.zip; do unzip -o $z; done echo ""## Produced images:"" >> release-notes.md echo "" "" >> release-notes.md cat *release.md | tee -a release-notes.md # Override the stage to run the release notes creation after the build of the images prepare-release-notes: stage: release # Override the stage to run the release notes creation after the build of the images create-release-notes: stage: release gitleaks: rules: - when: never # Customize gitleak job imported from to-be-continuous in order to checkout main # (needed for git to be able to retrieve commits from this branch not in main) gitleaks-custom: stage: gitleaks extends: gitleaks needs: [] before_script: - echo GITLEAKS_ARGS=$GITLEAKS_ARGS - !reference [gitleaks, before_script] variables: GITLEAKS_ARGS: '--verbose --log-opts=origin/main..HEAD' rules: - if: '$CI_PIPELINE_SOURCE == ""pipeline""' # Do not trigger gitleaks for cross-repo pipelines when: never - if: $CI_BRANCH_NAME == ""main"" variables: GITLEAKS_ARGS: '--verbose' # on main, detect leaks on whole repo - when: always .kubeadm_settings: variables: K8S_FLAVOR: kubeadm KANOD_OPTIONS_K8S: ""-b kubeadm"" parallel: matrix: - K8S_VERSION: # renovate: datasource=github-releases depName=kubernetes/kubernetes VersionTemplate=v - 1.29.9 # renovate: datasource=github-releases depName=kubernetes/kubernetes VersionTemplate=v - 1.28.14 # renovate: datasource=github-releases depName=kubernetes/kubernetes VersionTemplate=v - 1.27.16 .rke2_settings: variables: K8S_FLAVOR: rke2 KANOD_OPTIONS_K8S: ""-b rke2_airgapped"" parallel: matrix: - K8S_VERSION: # renovate: datasource=github-releases depName=rancher/rke2 VersionTemplate=v - 1.29.9-rke2r1 # renovate: datasource=github-releases depName=rancher/rke2 VersionTemplate=v - 1.28.14-rke2r1 # renovate: datasource=github-releases depName=rancher/rke2 VersionTemplate=v - 1.27.16-rke2r2 .ubuntu_settings: variables: OS: ubuntu OS_RELEASE: jammy .opensuse_settings: variables: OS: opensuse OS_RELEASE: ""15.5"" .default-trigger: trigger: include: .gitlab/ci/pipeline-build-and-test.yml strategy: depend forward: pipeline_variables: true rules: - if: $CI_COMMIT_TAG - if: $CI_PIPELINE_SOURCE == 'merge_request_event' && $CI_MERGE_REQUEST_LABELS =~ /AutoMerge/ - if: $CI_PIPELINE_SOURCE == 'merge_request_event' when: manual - if: $CI_PIPELINE_SOURCE == 'pipeline' when: manual build-ubuntu-hardened-rke2: extends: - .default-trigger - .rke2_settings - .ubuntu_settings variables: FLAVOR: hardened KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S -b cis_remediation"" build-ubuntu-plain-rke2: extends: - .default-trigger - .rke2_settings - .ubuntu_settings variables: FLAVOR: plain KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S"" build-ubuntu-plain-kubeadm: extends: - .default-trigger - .kubeadm_settings - .ubuntu_settings variables: FLAVOR: plain KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S"" build-opensuse-plain-rke2: extends: - .default-trigger - .rke2_settings - .opensuse_settings trigger: include: .gitlab/ci/pipeline-build-and-test-suse.yml strategy: depend variables: FLAVOR: plain KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S"" build-opensuse-plain-kubeadm: extends: - .default-trigger - .kubeadm_settings - .opensuse_settings trigger: include: .gitlab/ci/pipeline-build-and-test-suse.yml strategy: depend variables: FLAVOR: plain KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S"" build-opensuse-hardened-rke2: extends: - .default-trigger - .rke2_settings - .opensuse_settings trigger: include: .gitlab/ci/pipeline-build-and-test-suse.yml strategy: depend variables: FLAVOR: hardened KANOD_OPTIONS: ""$KANOD_OPTIONS_BASE $KANOD_OPTIONS_K8S -b cis_remediation_opensuse"" "; foreach (Match m in Regex.Matches(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