场景*memcache操作类

memcache操作类

在实际的PHP项目中，应用单例模式可以应用到网络连接的。比如Mysql、Memcache、Redis连接等等，一般的需求通常Redis，Memcache都只有一台服务器，所以用单例模式将连接封装到getInstance()，这样做的好处是不用每次都去调用connect()方法，减少网络连接开销。PHP大部分情况是单线程同步执行的，所以整个程序只用实例化一个Redis对象即可。

Memcache.php

<?php
class MemcacheClass
{
    private static $instance = null;

    private $handler;

    private function __construct($config)
    {
        if(!isset($config['host']))
        {
            $config['host'] = '127.0.0.1';
        }

        if(!isset($config['port']))
        {
            $config['port'] = 11211;
        }

        if(!isset($config['timeout']))
        {
            $config['timeout'] = 1;
        }

        $this->handler = new Memcache();
        $this->handler->connect($config['host'], $config['port'], $config['timeout']);
    }

    public static function init($config = array())
    {
        if (!self::$instance) {
            self::$instance = new self($config);
        }
        return self::$instance;
    }

    /**
     * get cache
     * @access public
     * @param string $name
     * @return mixed
     */
    public function get($name)
    {
        return $this->handler->get($name);
    }

    /**
     * set cache
     * @access public
     * @param string $name 
     * @param mixed $value
     * @param integer $expire
     * @return boolean
     */
    public function set($name, $value, $expire = 0)
    {
        $this->handler->set($name, $value, MEMCACHE_COMPRESSED, $expire);
    }

    /**
     * delete cache
     * @access public
     * @param string $name
     * @return boolean
     */
    public function rm($name, $ttl = false)
    {
        return $ttl === false ?
        $this->handler->delete($name) :
        $this->handler->delete($name, $ttl);
    }

    /**
     * flush cache
     * @access public
     * @return boolean
     */
    public function clear()
    {
        return $this->handler->flush();
    }

    function __destruct()
    {
        $this->handler->close();
    }
}

test.php

include 'Memcache.class.php';

$cache = MemcacheClass::init();