public static function getInstance() { if (NULL === self::$instance) { self::$instance = new self(); } return self::$instance; }
public static function getInstance() { if (self::$instance == null) { self::$instance = new singleton(); } return self::$instance; }
public static function getInstance(&$sql, $location, $var, $type) { // 确定类型 switch ($type) { default: // 默认使用字符串类型 // 默认使用字符串类型 case 'STRING': $var = addslashes($var); // 转义 $var = "'" . $var . "'"; // 加上单引号.sql语句中字符串插入必须加单引号 break; case 'INTEGER': case 'INT': $var = (int) $var; // 强制转换成int // 还可以增加更多的类型... } $pos = 0; // 判断该类是否是第一次被实例化 if (self::$instance == NULL) { self::$instance = new singleton(); for ($i = 1; $i <= $location; $i++) { $pos = strpos($sql, '?', $pos + 1); } } else { for ($i = 1; $i <= $location - 1; $i++) { $pos = strpos($sql, '?', $pos + 1); } } return $sql = substr($sql, 0, $pos) . $var . substr($sql, $pos + 1); }
/** * This function returns a instance (and creates a new one * if there isnt already one) of a class. * * @author Johannes Klose <*****@*****.**> * @param string $class Class from where an instance should be returned. * @return object Instance of $class **/ function &singleton($class) { static $singleton; if (!is_object($singleton)) { $singleton = new singleton(); } return $singleton->instance($class); }
public static function singleton($username, $password) { if (!(self::$instance)) { $className = __CLASS__; self::$instance = new Mongo("mongodb://${username}:${password}@localhost/test", array("persist" => "x")); ; } return self::$instance; }