/**
* 取得数据库类实例
* @static
* @access public
* @param mixed $config 连接配置
* @return Object 返回数据库驱动类
*/
public static function getInstance($config = array())
{
$md5 = md5(serialize($config));
if (!isset(self::$instance[$md5])) {
// 解析连接参数 支持数组和字符串
$options = self::parseConfig($config);
// 兼容mysqli
if ('mysqli' == $options['type']) {
$options['type'] = 'mysql';
}
// 如果采用lite方式 仅支持原生SQL 包括query和execute方法
$class = !empty($options['lite']) ? 'Core\\db\\Lite' : 'Core\\db\\driver\\' . ucwords(strtolower($options['type']));
if (class_exists($class)) {
self::$instance[$md5] = new $class($options);
} else {
// 类没有定义
//TODO E(L('_NO_DB_DRIVER_').': ' . $class);
}
}
self::$_instance = self::$instance[$md5];
return self::$_instance;
}
/**
* @param string $host
* @param string $username
* @param string $password
* @param string $db
* @param int $port
* @param string $charset
*/
public function __construct($host = null, $username = null, $password = null, $db = null, $port = null, $charset = 'utf8')
{
$isSubQuery = false;
// if params were passed as array
if (is_array($host)) {
foreach ($host as $key => $val) {
${$key} = $val;
}
}
// if host were set as mysqli socket
if (is_object($host)) {
$this->_mysqli = $host;
} else {
$this->host = $host;
}
$this->username = $username;
$this->password = $password;
$this->db = $db;
$this->port = $port;
$this->charset = $charset;
if ($isSubQuery) {
$this->isSubQuery = true;
return;
}
if (isset($prefix)) {
$this->setPrefix($prefix);
}
self::$_instance = $this;
}
