strstr - PHP code example

PHP Function Strstr - Getting the First Occurrence of a Substring in a String

PHP strstr is a string function that finds the first occurrence of a substring inside another string. It returns the rest of the string (from the matching point), or FALSE, if the search string is not found in the given string. It is also a binary safe function, meaning it can be used on files without modifying them.

Often times, you may need to validate that an email address or a URL contains a specific word or letter. This could be as simple as ensuring that the string is properly formatted by searching for a specific character, or it could be something more complicated like checking whether a string contains a certain character pattern.

The php function strstr and its case-insensitive version, stristr, are the perfect tools to help you do this. They both find the first occurrence of a substring within a string, but they differ in how they do so. In this article, we will explore the use cases and syntax for strstr and stristr, giving you an in-depth look at their functionality.

Input string: $string. Substring: $needle. Output string: if ($needle not in string): return FALSE. else: return str(string[1:]+"".join((string[:needle].replace("?",""))+string[needle+1:])

strstr example

return false;
        }
        fputs($fp, $request);
        $contents = '';
        $debugContents = '';
        $gotFirstLine = false;
        $gettingHeaders = true;
        while (!feof($fp)) {
            $line = fgets($fp, 4096);
            if (!$gotFirstLine) {
                // Check line for '200'                 if (strstr($line, '200') === false) {
                    $this->error = new IXR_Error(-32300, 'transport error - HTTP status code was not 200');
                    return false;
                }
                $gotFirstLine = true;
            }
            if (trim($line) == '') {
                $gettingHeaders = false;
            }
            if (!$gettingHeaders) {
                // merged from WP #12559 - remove trim                 $contents .= $line;
            }

/* translators: %s: URL to Plugins screen. */
            __( 'Please <a href="%s">deactivate your plugins</a> before enabling the Network feature.' ),
            admin_url( 'plugins.php?plugin_status=active' )
        ) . '</p></div>';
        echo '<p>' . __( 'Once the network is created, you may reactivate your plugins.' ) . '</p>';
        echo '</div>';
        require_once ABSPATH . 'wp-admin/admin-footer.php';
        die();
    }

    $hostname  = get_clean_basedomain();
    $has_ports = strstr( $hostname, ':' );
    if ( ( false !== $has_ports && ! in_array( $has_ports, array( ':80', ':443' ), true ) ) ) {
        echo '<div class="error"><p><strong>' . __( 'Error:' ) . '</strong> ' . __( 'You cannot install a network of sites with your server address.' ) . '</p></div>';
        echo '<p>' . sprintf(
            /* translators: %s: Port number. */
            __( 'You cannot use port numbers such as %s.' ),
            '<code>' . $has_ports . '</code>'
        ) . '</p>';
        echo '<a href="' . esc_url( admin_url() ) . '">' . __( 'Go to Dashboard' ) . '</a>';
        echo '</div>';
        require_once ABSPATH . 'wp-admin/admin-footer.php';
        die();
    }

  public static function assertAllMatch($pattern, $traversable, $case_sensitive = FALSE) {
    if (static::assertTraversable($traversable)) {
      if ($case_sensitive) {
        foreach ($traversable as $member) {
          if (!(is_string($member) && strstr($member, $pattern))) {
            return FALSE;
          }
        }
      }
      else {
        foreach ($traversable as $member) {
          if (!(is_string($member) && stristr($member, $pattern))) {
            return FALSE;
          }
        }
      }

$area = Package::getPackageName($class);
            } catch (\Throwable $e) {
                $areas['unknown'][$class] = $path;

                continue;
            }

            if (!\is_string($area)) {
                continue;
            }

            $areaTrim = strstr($area, \PHP_EOL, true) ?: $area;

            $areas[trim($areaTrim)][$class] = $path;
        }

        return $areas;
    }

    /** * @return array<string, string> */
    private function getShopwareClasses(): array
    {

    /** * Replace any constants referenced in a string with their values * * @param string $value * @return string */
    protected function _replaceConstants($value)
    {
        foreach ($this->_getConstants() as $constant) {
            if (strstr($value, $constant)) {
                // handle backslashes that may represent windows path names for instance                 $replacement = str_replace('\\', '\\\\', constant($constant));
                $value = str_replace($constant, $replacement, $value);
            }
        }
        return $value;
    }

    /** * Get (reverse) sorted list of defined constant names * * @return array */

        $locale = $parameters['_locale']
            ?? $this->context->getParameter('_locale')
            ?: $this->defaultLocale;

        if (null !== $locale) {
            do {
                if (($this->compiledRoutes[$name.'.'.$locale][1]['_canonical_route'] ?? null) === $name) {
                    $name .= '.'.$locale;
                    break;
                }
            } while (false !== $locale = strstr($locale, '_', true));
        }

        if (!isset($this->compiledRoutes[$name])) {
            throw new RouteNotFoundException(sprintf('Unable to generate a URL for the named route "%s" as such route does not exist.', $name));
        }

        [$variables, $defaults, $requirements, $tokens, $hostTokens, $requiredSchemes, $deprecations] = $this->compiledRoutes[$name] + [6 => []];

        foreach ($deprecations as $deprecation) {
            trigger_deprecation($deprecation['package'], $deprecation['version'], $deprecation['message']);
        }

foreach ($thisfile_id3v2['comments']['genre'] as $key => $value) {
                foreach ($this->ParseID3v2GenreString($value) as $genre) {
                    $genres[] = $genre;
                }
            }
            $thisfile_id3v2['comments']['genre'] = array_unique($genres);
            unset($key, $value, $genres, $genre);
        }

        if (isset($thisfile_id3v2['comments']['track_number'])) {
            foreach ($thisfile_id3v2['comments']['track_number'] as $key => $value) {
                if (strstr($value, '/')) {
                    list($thisfile_id3v2['comments']['track_number'][$key], $thisfile_id3v2['comments']['totaltracks'][$key]) = explode('/', $thisfile_id3v2['comments']['track_number'][$key]);
                }
            }
        }

        if (!isset($thisfile_id3v2['comments']['year']) && !empty($thisfile_id3v2['comments']['recording_time'][0]) && preg_match('#^([0-9]{4})#', trim($thisfile_id3v2['comments']['recording_time'][0]), $matches)) {
            $thisfile_id3v2['comments']['year'] = array($matches[1]);
        }

        if (!empty($thisfile_id3v2['TXXX'])) {

$this->_flushGroup($tag);
    }
    foreach ($words as $word) {
      // new-line should only come as first char of word.       if ($word == '') {
        continue;
      }
      if ($word[0] == "\n") {
        $this->_flushLine($tag);
        $word = mb_substr($word, 1);
      }
      assert(!strstr($word, "\n"));
      $this->group .= $word;
    }
  }

  public function getLines() {
    $this->_flushLine('~done');
    return $this->lines;
  }

}

continue;
                }

                $supportedTypes = $normalizer->getSupportedTypes($format);

                $doesClassRepresentCollection = str_ends_with($class, '[]');

                foreach ($supportedTypes as $supportedType => $isCacheable) {
                    if (\in_array($supportedType, ['*', 'object'], true)
                        || $class !== $supportedType && ('object' !== $genericType || !is_subclass_of($class, $supportedType))
                        && !($doesClassRepresentCollection && str_ends_with($supportedType, '[]') && is_subclass_of(strstr($class, '[]', true), strstr($supportedType, '[]', true)))
                    ) {
                        continue;
                    }

                    if (null === $isCacheable) {
                        unset($supportedTypes['*'], $supportedTypes['object']);
                    } elseif ($this->denormalizerCache[$format][$class][$k] = $isCacheable && $normalizer->supportsDenormalization(null, $class, $format, $context)) {
                        break 2;
                    }

                    break;
                }

            $PossibleLAMEversionStringOffset = $info['avdataend'] - $PossiblyLongerLAMEversion_FrameLength;
            $this->fseek($PossibleLAMEversionStringOffset);
            $PossiblyLongerLAMEversion_Data = $this->fread($PossiblyLongerLAMEversion_FrameLength);
            switch (substr($CurrentDataLAMEversionString, -1)) {
                case 'a':
                case 'b':
                    // "LAME3.94a" will have a longer version string of "LAME3.94 (alpha)" for example                     // need to trim off "a" to match longer string                     $CurrentDataLAMEversionString = substr($CurrentDataLAMEversionString, 0, -1);
                    break;
            }
            if (($PossiblyLongerLAMEversion_String = strstr($PossiblyLongerLAMEversion_Data, $CurrentDataLAMEversionString)) !== false) {
                if (substr($PossiblyLongerLAMEversion_String, 0, strlen($CurrentDataLAMEversionString)) == $CurrentDataLAMEversionString) {
                    $PossiblyLongerLAMEversion_NewString = substr($PossiblyLongerLAMEversion_String, 0, strspn($PossiblyLongerLAMEversion_String, 'LAME0123456789., (abcdefghijklmnopqrstuvwxyzJFSOND)')); //"LAME3.90.3" "LAME3.87 (beta 1, Sep 27 2000)" "LAME3.88 (beta)"                     if (empty($info['audio']['encoder']) || (strlen($PossiblyLongerLAMEversion_NewString) > strlen($info['audio']['encoder']))) {
                        if (!empty($info['audio']['encoder']) && !empty($info['mpeg']['audio']['LAME']['short_version']) && ($info['audio']['encoder'] == $info['mpeg']['audio']['LAME']['short_version'])) {
                            if (preg_match('#^LAME[0-9\\.]+#', $PossiblyLongerLAMEversion_NewString, $matches)) {
                                // "LAME3.100" -> "LAME3.100.1", but avoid including "(alpha)" and similar                                 $info['mpeg']['audio']['LAME']['short_version'] = $matches[0];
                            }
                        }
                        $info['audio']['encoder'] = $PossiblyLongerLAMEversion_NewString;
                    }
                }

        // shortcut         $info['replay_gain'] = array();
        $thisfile_replaygain = &$info['replay_gain'];

        for ($i = 0; $i < $thisfile_ape['footer']['raw']['tag_items']; $i++) {
            $value_size = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));
            $offset += 4;
            $item_flags = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));
            $offset += 4;
            if (strstr(substr($APEtagData, $offset), "\x00") === false) {
                $this->error('Cannot find null-byte (0x00) separator between ItemKey #'.$i.' and value. ItemKey starts '.$offset.' bytes into the APE tag, at file offset '.($thisfile_ape['tag_offset_start'] + $offset));
                return false;
            }
            $ItemKeyLength = strpos($APEtagData, "\x00", $offset) - $offset;
            $item_key      = strtolower(substr($APEtagData, $offset, $ItemKeyLength));

            // shortcut             $thisfile_ape['items'][$item_key] = array();
            $thisfile_ape_items_current = &$thisfile_ape['items'][$item_key];

            $thisfile_ape_items_current['offset'] = $thisfile_ape['tag_offset_start'] + $offset;

    protected static function _parseShortOption($arg, $short_options, &$opts, &$argIdx, $args, $skip_unknown)
    {
        for ($i = 0; $i < strlen($arg); $i++) {
            $opt     = $arg[$i];
            $opt_arg = null;

            /* Try to find the short option in the specifier string. */
            if (($spec = strstr($short_options, $opt)) === false || $arg[$i] == ':') {
                if ($skip_unknown === true) {
                    break;
                }

                $msg = "Console_Getopt: unrecognized option -- $opt";
                return PEAR::raiseError($msg);
            }

            if (strlen($spec) > 1 && $spec[1] == ':') {
                if (strlen($spec) > 2 && $spec[2] == ':') {
                    if ($i + 1 < strlen($arg)) {

        return $this->config['type'];
    }

    /** * {@inheritdoc} */
    public function listFiles($directory = '')
    {
        $files = [];
        foreach ($this->filesystem->listContents($directory, true) as $file) {
            if ($file['type'] === 'dir' || strstr($file['path'], '/.') !== false) {
                continue;
            }

            $files[] = $file['path'];
        }

        return $files;
    }

    /** * {@inheritdoc} */

        if (!isset($params['width'])) {
            $width = $_image_data[0];
        }
        if (!isset($params['height'])) {
            $height = $_image_data[1];
        }
    }

    if (isset($params['dpi'])) {
        if (strstr($_SERVER['HTTP_USER_AGENT'], 'Mac')) {
            // FIXME: (rodneyrehm) wrong dpi assumption             // don't know who thought this up… even if it was true in 1998, it's definitely wrong in 2011.             $dpi_default = 72;
        } else {
            $dpi_default = 96;
        }
        $_resize = $dpi_default / $params['dpi'];
        $width = round($width * $_resize);
        $height = round($height * $_resize);
    }

          $this->errors[] = new FormattableMarkup('The translation stream %uri contains an error: "msgstr[]" is unexpected on line %line.', $log_vars);
          return FALSE;
        }

        // Ensure the plurality is terminated.         if (!str_contains($line, ']')) {
          $this->errors[] = new FormattableMarkup('The translation stream %uri contains an error: invalid format for "msgstr[]" on line %line.', $log_vars);
          return FALSE;
        }

        // Extract the plurality.         $frombracket = strstr($line, '[');
        $this->currentPluralIndex = substr($frombracket, 1, strpos($frombracket, ']') - 1);

        // Skip to the next whitespace and trim away any further whitespace,         // bringing $line to the message text only.         $line = trim(strstr($line, " "));

        $quoted = $this->parseQuoted($line);
        if ($quoted === FALSE) {
          // The string must be quoted.           $this->errors[] = new FormattableMarkup('The translation stream %uri contains an error: invalid format for "msgstr[]" on line %line.', $log_vars);
          return FALSE;
        }