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

/
/
sU

Test String

Code Generator

Generated Code

const regex = /<xf:tokeninputrow.*\/>/s; // Alternative syntax using RegExp constructor // const regex = new RegExp('<xf:tokeninputrow.*\\\/>', 's') const str = `<xf:title>{{ phrase('start_conversation') }}</xf:title> <xf:breadcrumb href="{{ link('conversations') }}">{{ phrase('conversations') }}</xf:breadcrumb> <xf:if contentcheck="true"> <div class="blockMessage blockMessage--error blockMessage--iconic"> <xf:contentcheck> <xf:if is="\$errorUsernames is not empty"> <div>{{ phrase('you_can_not_start_conversation_with_following_users_because_of_privacy', {'usernames': \$errorUsernames|join(', ')}) }}</div> </xf:if> <xf:if is="\$notFoundUsernames is not empty"> <div>{{ phrase('following_users_not_found_x', {'usernames': \$notFoundUsernames|join(', ')}) }}</div> </xf:if> <xf:if is="\$recipientLimit"> <div>{{ phrase('you_have_exceeded_allowed_number_of_recipients_x_for', {'limit': \$recipientLimit}) }}</div> </xf:if> </xf:contentcheck> </div> </xf:if> <xf:form action="{{ link('conversations/add') }}" ajax="true" draft="{{ link('conversations/draft') }}" data-preview-url="{{ link('conversations/add-preview') }}" class="block" data-xf-init="attachment-manager"> <div class="block-container"> <div class="block-body"> <xf:tokeninputrow name="recipients" value="{\$to}" href="{{ link('members/find') }}" rowtype="fullWidth" label="{{ phrase('recipients') }}" explain="{{ phrase('separate_names_with_comma') }}" /> <xf:textboxrow name="title" value="{\$title}" rowtype="fullWidth noLabel" class="input--title" maxlength="{{ max_length('XF:ConversationMaster', 'title') }}" placeholder="{{ phrase('title...') }}" label="{{ phrase('title') }}" /> <xf:editorrow name="message" value="{\$message}" attachments="{{ \$attachmentData ? \$attachmentData.attachments : [] }}" rowtype="fullWidth noLabel mergePrev" /> <xf:formrow> <xf:if is="\$attachmentData"> <xf:macro template="helper_attach_upload" name="upload_block" arg-attachmentData="{\$attachmentData}" arg-forceHash="{\$draft.attachment_hash}" /> </xf:if> <xf:if is="\$xf.options.multiQuote"> <xf:macro template="multi_quote_macros" name="button" arg-href="{{ link('conversations/multi-quote', \$conversation) }}" arg-messageSelector=".js-message" arg-storageKey="multiQuoteConversation" /> </xf:if> <xf:button class="button--link u-jsOnly" data-xf-click="preview-click" icon="preview" /> </xf:formrow> <xf:checkboxrow> <xf:option name="open_invite" checked="{{ (\$draft.open_invite OR \$conversation.open_invite) ? 'checked' : '' }}"> {{ phrase('allow_anyone_in_conversation_to_invite_others') }} </xf:option> <xf:option name="conversation_locked" checked="{{ (\$draft.conversation_open OR \$conversation.conversation_open) ? '' : 'checked' }}"> {{ phrase('lock_conversation_no_responses_will_be_allowed') }} </xf:option> </xf:checkboxrow> </div> <xf:submitrow submit="{{ phrase('start_conversation') }}" sticky="true" icon="conversation"> <xf:html> <xf:button class="u-jsOnly" data-xf-click="preview-click" icon="preview" /> </xf:html> </xf:submitrow> </div> </xf:form>`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions