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

/
/
gis

Test String

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r#"(?is)^(?:[[:^print:][:cntrl:]\s]|GIF89.{0,20})*(?:<[^>]+>\s*)+<title>contador\s*de \s*acessos<\/title>.{0,1350}?\$caminho\s*=\s*"contador\.txt.{0,150}?\$arquivo\s*=\s*fopen\(\$caminho.{0,150}?numero\s*de\s*visitas\s*fclose\(\$arquivo.{0,650}?<meta.{0,50}?url=['"]contador\.php.{0,50}?\/html[[:punct:]\s]+$"#).unwrap(); let string = "<html> <head> <title>Contador de Acessos</title> <meta http-equiv=\"Content-Type\" content=\"text/html; charset=iso-8859-1\"><style type=\"text/css\"> <!-- body,td,th { color: #FF0000; font-family: Verdana; font-size: 12px; } body { background-color: #CCCCCC; } .style1 { font-size: 15px; font-weight: bold; } .style2 { font-size: 12px; color: #FF0000; } .style3 { font-size: 15px; color: #000000; } .style4 {color: #000000} .style5 {font-size: 15px; font-weight: bold; color: #000000; } .style8 {font-size: 24px; font-weight: bold; } .style9 {color: #CCCCCC} .style11 {color: #FF0000} .style12 {color: #FFFFFF} .style15 {color: #FFFFFF; font-size: 20px; } --> </style><body link=\"#FF0000\" vlink=\"#FF0000\" alink=\"#FF0000\"> <center> <table width=\"476\" border=\"0\"> <tr> <td width=\"470\" bgcolor=\"#000000\"><div align=\"center\"><span class=\"style15\"> CONTADOR - <span class=\"style11\">BB</span></span> </div></td> </tr> </table> <p><span class=\"style5\"> $$ CONTADOR DE ACESSOS $$ <br> <br> <span class=\"style2\">==========================================================</span><br> </span><br> <span class=\"style4\">VOC&Ecirc; POSSUI<span class=\"style9\">-</span> </span> </h1> <span class=\"style8\"> <?php $caminho = \"contador.txt\";//nome do arquivo que vai guardar os visitantes $arquivo = fopen($caminho, \"r\");//abre o arquivo $total = fgets($arquivo,1024); //pega o numero de visitas fclose($arquivo);//fecha o arquivo $x = $total; echo \"\" . $x;//mostra na tela o numero de visitantes ?> </span> <span class=\"style4\"> CLIQUES.</span> <br> <br> <br> <br> <span class=\"style4\"><strong>OBS:</strong> A P&Aacute;GINA FICA ATUALIZANDO AUTOMATICAMENTE EM 60 SEGUNDOS. </span></p> <table width=\"568\" border=\"0\"> <tr> <td bgcolor=\"#000000\"><div align=\"center\"><span class=\"style12\">CONTADOR SPAM<span class=\"style11\"></span></span></div></td> </tr> </table> <p><br> </p> <meta http-equiv='Refresh' content='60'; URL='contador.php'> </center> </body> </head> </html>"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/