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

~
~
gxuJ

Test String

Code Generator

Generated Code

$re = '~<url>\s* (?> (?> (?><lastmod>\s*(?<mod>[^<]+)\s*</lastmod>) | (?><changefreq>\s*(?<freq>\w+)\s*</changefreq>) | (?><priority>\s*(?<prio>[01](?>\.\d{1,2})?)\s*</priority>) )\s* ){0,3}\s* <loc>\s* (?<uri>[^<]+)\s* </loc>\s* (?> (?> (?><lastmod>\s*(?<mod>[^<]+)\s*</lastmod>) | (?><changefreq>\s*(?<freq>\w+)\s*</changefreq>) | (?><priority>\s*(?<prio>[01](?>\.\d{1,2})?)\s*</priority>) )\s* ){0,3}\s* </url>~xuJ'; $str = '<?xml version="1.0" encoding="UTF-8"?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"> <url> <lastmod>2005-01-01</lastmod> <changefreq>monthly</changefreq> <priority>0.8</priority> <loc>http://www.example.com/</loc> </url> <url> <loc>http://www.example.com/catalog?item=12&amp;desc=vacation_hawaii</loc> <changefreq>weekly</changefreq> </url> <url> <loc>http://www.example.com/catalog?item=73&amp;desc=vacation_new_zealand</loc> <lastmod>2004-12-23</lastmod> <changefreq>weekly</changefreq> </url> <url> <loc>http://www.example.com/catalog?item=74&amp;desc=vacation_newfoundland</loc> <lastmod>2004-12-23T18:00:15+00:00</lastmod> <priority>0.3</priority> </url> <url> <loc>http://www.example.com/catalog?item=83&amp;desc=vacation_usa</loc> <lastmod>2004-11-23</lastmod> </url> </urlset>'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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