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

/
/
gm

Test String

Code Generator

Generated Code

$re = '/maxiobe request response game/m'; $str = 'index.php: <?php // index.php – Aufgabe 3 (Bootstrap, Bereichsauswahl, Validierung, Versuchszähler) declare(strict_types=1); session_start(); /* ------------------ Helper ------------------ */ function h(string $s): string { return htmlspecialchars($s, ENT_QUOTES, \'UTF-8\'); } function resetGame(): void { unset($_SESSION[\'randomNumber\'], $_SESSION[\'tries\'], $_SESSION[\'min\'], $_SESSION[\'max\'], $_SESSION[\'guesses\']); } /* ------------------ Init ------------------ */ $alerts = []; // sammelt Bootstrap-Alerts [ [\'type\'=>\'warning|danger|success|info\',\'text\'=>\'...\'] ] if (!isset($_SESSION[\'tries\'])) { $_SESSION[\'tries\'] = 0; } if (!isset($_SESSION[\'guesses\'])) { $_SESSION[\'guesses\'] = []; } /* ------------------ Actions ------------------ */ if ($_SERVER[\'REQUEST_METHOD\'] === \'POST\') { // Exit / Neues Spiel if (isset($_POST[\'exit\'])) { resetGame(); header(\'Location: \' . $_SERVER[\'SCRIPT_NAME\']); exit(); } // Start-Spiel mit Bereich (min/max) if (isset($_POST[\'startgame\'])) { $min = $_POST[\'min\'] ?? \'1\'; $max = $_POST[\'max\'] ?? \'10\'; // Grundvalidierung: ganzzahlig $validInts = ctype_digit(strval($min)) && ctype_digit(strval($max)); if (!$validInts) { $alerts[] = [\'type\'=>\'danger\',\'text\'=>\'Bitte nur ganze Zahlen für <b>Min</b> und <b>Max</b> verwenden.\']; } else { $min = (int)$min; $max = (int)$max; // Logische Prüfungen if ($min < 0) { $alerts[] = [\'type\'=>\'warning\',\'text\'=>\'Der Minimalwert darf nicht negativ sein.\']; } if ($max <= $min) { $alerts[] = [\'type\'=>\'warning\',\'text\'=>\'<b>Max</b> muss größer als <b>Min</b> sein.\']; } if ($max - $min > 10000) { $alerts[] = [\'type\'=>\'warning\',\'text\'=>\'Der Bereich ist zu groß. Wähle einen kleineren Abstand (max. 10.000).\']; } if (!$alerts) { $_SESSION[\'min\'] = $min; $_SESSION[\'max\'] = $max; $_SESSION[\'randomNumber\'] = rand($min, $max); $_SESSION[\'tries\'] = 0; $_SESSION[\'guesses\'] = []; $alerts[] = [\'type\'=>\'primary\',\'text\'=>"Spiel gestartet! Rate die Zahl zwischen <b>{$min}</b> und <b>{$max}</b>."]; } } } // Rateversuch if (isset($_POST[\'try\']) && isset($_SESSION[\'randomNumber\'])) { $raw = $_POST[\'enteredNumber\'] ?? \'\'; // Prüfung: Zahl eingegeben? if ($raw === \'\' || !preg_match(\'/^-?\\d+$/\', trim((string)$raw))) { $alerts[] = [\'type\'=>\'warning\',\'text\'=>\'Bitte eine <b>ganze Zahl</b> eingeben.\']; } else { $guess = (int)$raw; $min = $_SESSION[\'min\'] ?? 1; $max = $_SESSION[\'max\'] ?? 10; // Bereichsprüfung if ($guess < $min || $guess > $max) { $alerts[] = [\'type\'=>\'warning\',\'text\'=>"Dein Tipp liegt <b>außerhalb</b> des Bereichs <b>{$min}–{$max}</b>."]; } else { $secret = (int)$_SESSION[\'randomNumber\']; $_SESSION[\'tries\']++; $_SESSION[\'guesses\'][] = $guess; if ($guess === $secret) { $t = (int)$_SESSION[\'tries\']; $alerts[] = [\'type\'=>\'success\',\'text\'=>"Zahl erraten 🎉 – du brauchtest <b>{$t}</b> Versuch" . ($t === 1 ? \'\' : \'e\') . "."]; // Nach Erfolg: Neues Spiel möglich (Reset-Button rendern), Zahl bleibt aber bis Exit, // damit man die Success-Meldung sieht und "Neues Spiel" klicken kann. // Alternativ direkt resetGame(); echo Link – aber wir bleiben konsistent mit Aufgabe 2. } else { $hint = ($guess > $secret) ? \'zu hoch\' : \'zu niedrig\'; $alerts[] = [\'type\'=>\'danger\',\'text\'=>"Leider falsch – dein Tipp ist <b>{$hint}</b>."]; } } } } } /* ------------------ View (HTML) ------------------ */ ?> <!doctype html> <html lang="de"> <head> <meta charset="utf-8"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>Ratespiel – Aufgabe 3</title> <link rel="stylesheet" href="assets/bootstrap/css/bootstrap.min.css"> </head> <body> <div class="container py-4"> <h1 class="mb-4">Ratespiel – Aufgabe 3</h1> <?php foreach ($alerts as $a): ?> <div class="alert alert-<?php echo h($a[\'type\']); ?>" role="alert"> <?php echo $a[\'text\']; ?> </div> <?php endforeach; ?> <?php if (isset($_SESSION[\'randomNumber\'])): ?> <!-- Laufendes Spiel --> <div class="card mb-3"> <div class="card-body"> <h5 class="card-title">Dein Tipp</h5> <form class="row g-3" action="<?php echo h($_SERVER[\'SCRIPT_NAME\']); ?>" method="post" name="form"> <div class="col-sm-6 col-md-4"> <input class="form-control" type="number" name="enteredNumber" placeholder="Zahl <?php echo (int)($_SESSION[\'min\'] ?? 1); ?>–<?php echo (int)($_SESSION[\'max\'] ?? 10); ?>" min="<?php echo (int)($_SESSION[\'min\'] ?? 1); ?>" max="<?php echo (int)($_SESSION[\'max\'] ?? 10); ?>"> </div> <div class="col-auto"> <button class="btn btn-success" type="submit" name="try" value="1">Raten</button> </div> <div class="col-auto"> <button class="btn btn-outline-secondary" type="submit" name="exit" value="1">Neues Spiel</button> </div> </form> <p class="mt-3 mb-0"> Bereich: <span class="badge bg-secondary"> <?php echo (int)($_SESSION[\'min\'] ?? 1); ?>–<?php echo (int)($_SESSION[\'max\'] ?? 10); ?> </span> &nbsp;|&nbsp; Versuche: <span class="badge bg-info text-dark"><?php echo (int)$_SESSION[\'tries\']; ?></span> </p> <?php if (!empty($_SESSION[\'guesses\'])): ?> <p class="mt-2 mb-0"> Bisherige Tipps: <?php foreach ($_SESSION[\'guesses\'] as $g): ?> <span class="badge bg-light text-dark"><?php echo (int)$g; ?></span> <?php endforeach; ?> </p> <?php endif; ?> </div> </div> <?php if (!empty($alerts) && end($alerts)[\'type\'] === \'success\'): ?> <!-- Bei Erfolg optional Hinweis-Card --> <div class="alert alert-success" role="alert"> Glückwunsch! Du kannst oben auf <b>Neues Spiel</b> klicken, um erneut zu starten. </div> <?php endif; ?> <?php else: ?> <!-- Startseite mit Bereichsauswahl --> <div class="card"> <div class="card-body"> <h5 class="card-title">Spiel starten</h5> <form class="row g-3" action="<?php echo h($_SERVER[\'SCRIPT_NAME\']); ?>" method="post" name="form"> <div class="col-sm-4 col-md-3"> <label class="form-label" for="min">Min</label> <input class="form-control" type="number" id="min" name="min" value="1" min="0" step="1" required> </div> <div class="col-sm-4 col-md-3"> <label class="form-label" for="max">Max</label> <input class="form-control" type="number" id="max" name="max" value="10" min="1" step="1" required> </div> <div class="col-12"> <button class="btn btn-primary" type="submit" name="startgame" value="1">Spielstart</button> </div> </form> <p class="text-muted mt-2 mb-0">Tipp: Wähle z. B. 1–100 für mehr Herausforderung.</p> </div> </div> <?php endif; ?> </div> <script src="assets/bootstrap/js/bootstrap.bundle.min.js"></script> </body> </html> form try: <?php // form_try.part.php ?> <form action="<?php echo htmlspecialchars($_SERVER[\'SCRIPT_NAME\']); ?>" method="post" name="form"> <input type="text" name="enteredNumber" placeholder="Zahl zwischen 1 und 10" /> <input type="submit" value="Raten" name="try" /> <input type="submit" value="Exit" name="exit" /> </form> form start: <?php // form_start.part.php ?> <form action="<?php echo htmlspecialchars($_SERVER[\'SCRIPT_NAME\']); ?>" method="post" name="form"> <input type="submit" value="Spielstart" name="startgame" /> </form> '; preg_match_all($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