'127.0.0.1', 'user' => 'root', 'password' => '', 'database' => 'video', ); private function __construct() { } static public function getinstance() { if(!(self::$_instance instanceof self)) { self::$_instance = new self(); } return self::$_instance; } public function connect() { if(!self::$_connectsource) { self::$_connectsource = @mysql_connect($this->_dbconfig['host'], $this->_dbconfig['user'], $this->_dbconfig['password']); if(!self::$_connectsource) { throw new exception('mysql connect error ' . mysql_error()); //die('mysql connect error' . mysql_error());} mysql_select_db($this->_dbconfig['database'], self::$_connectsource); mysql_query(set names utf8, self::$_connectsource); } return self::$_connectsource; }}/*$connect = db::getinstance()->connect();$sql = select * from video;$result = mysql_query($sql, $connect);echo mysql_num_rows($result);var_dump($result);*/

以上就介绍了 singleton单例模式，包括了方面的内容，希望对php教程有兴趣的朋友有所帮助。