php 代码均来源于《PHP设计模式》一书(3)

Interpreter.class.php ~ 2KB    下载(20)

<?php
/**
 * 转自 《PHP设计模式》 第十章： 解释器模式
 * 解释器： 解释器设计模式用于分析一个实体的关键元素，并且针对每个元素都提供自己的解释或相应的动作。
 * 解释器设计模式最常用于PHP/HTML 模板系统。
 *
 */
class User {

    protected $_username = "";

    public function __construct($username) {
        $this->_username = $username;
    }

    public function getProfilePage() {
        $profile  = "<h2>I like Never Again ! </h2>";
        $profile .= "I love all of their songs. My favorite CD: <br />";
        $profile .= "{{myCD.getTitle}}!!";

        return $profile;
    }
}

class userCD {

    protected $_user = NULL;

    public function setUser(User $user) {
        $this->_user = $user;
    }

    public function getTitle() {
        $title = "Waste of a Rib";

        return $title;
    }
}

class userCDInterpreter {

    protected $_user = NULL;

    public function setUser(User $user) {
        $this->_user = $user;
    }

    public function getInterpreted() {
        $profile = $this->_user->getProfilePage();

        if (preg_match_all('/\{\{myCD\.(.*?)\}\}/', $profile, $triggers, PREG_SET_ORDER)) {
            $replacements = array();

            foreach ($triggers as $trigger) {
                $replacements[] = $trigger[1];
            }

            $replacements = array_unique($replacements);

            $myCD = new userCD();
            $myCD->setUser($this->_user);

            foreach ($replacements as $replacement) {
                $profile = str_replace("{{myCD.{$replacement}}}", call_user_func(array($myCD, $replacement)), $profile);
            }
        }

        return $profile;
    }

}

$username = "aaron";
$user = new User($username);
$interpreter = new userCDInterpreter();
$interpreter->setUser($user);

print "<h1>{$username}'s Profile</h1>";
print $interpreter->getInterpreted();

/* End of Interpreter.class.php */
/* Location the file Design/Interpreter.class.php */

Iterator.class.php ~ 2KB    下载(19)

<?php
/**
 * 转自 《PHP设计模式》 第十一章： 迭代器模式
 * 迭代器：迭代器设计模式可帮助构造特定对象， 那些对象能够提供单一标准接口循环或迭代任何类型的可计数数据。
 * 处理需要遍历的可计数数据时， 最佳的解决办法是创建一个基于迭代器设计模式的对象。
 *
 */
class CD {

    public $band  = "";
    public $title = "";
    public $trackList = array();

    public function __construct($band, $title) {
        $this->band  = $band;
        $this->title = $title;
    }

    public function addTrack($track) {
        $this->trackList[] = $track;
    }
}

class CDSearchByBandIterator implements Iterator {

    private $_CDs   = array();
    private $_valid = FALSE;

    public function __construct($bandName) {
        $db = mysql_connect("localhost", "root", "root");
        mysql_select_db("test");

        $sql  = "select CD.id, CD.band, CD.title, tracks.tracknum, tracks.title as tracktitle ";
        $sql .= "from CD left join tracks on CD.id = tracks.cid ";
        $sql .= "where band = '" . mysql_real_escape_string($bandName) . "' ";
        $sql .= "order by tracks.tracknum";

        $results = mysql_query($sql);

        $cdID = 0;
        $cd   = NULL;

        while ($result = mysql_fetch_array($results)) {
            if ($result["id"] !== $cdID) {
                if ( ! is_null($cd)) {
                    $this->_CDs[] = $cd;
                }

                $cdID = $result['id'];
                $cd   = new CD($result['band'], $result['title']);
            }

            $cd->addTrack($result['tracktitle']);
        }

        $this->_CDs[] = $cd;
    }

    public function next() {
        $this->_valid = (next($this->_CDs) === FALSE) ? FALSE : TRUE;
    }

    public function rewind() {
        $this->_valid = (reset($this->_CDs) === FALSE) ? FALSE : TRUE;
    }

    public function valid() {
        return $this->_valid;
    }

    public function current() {
        return current($this->_CDs);
    }

    public function key() {
        return key($this->_CDs);
    }
}

$queryItem = "Never Again";

$cds = new CDSearchByBandIterator($queryItem);

print "<h1>Found the Following CDs</h1>";
print "<table border='1'><tr><th>Band</th><th>Ttile</th><th>Num Tracks</th></tr>";
foreach ($cds as $cd) {
    print "<tr><td>{$cd->band}</td><td>{$cd->title}</td><td>";
    print count($cd->trackList). "</td></tr>";
}
print "</table>";

/* End of Iterator.class.php */
/* Location the file Design/Iterator.class.php */