自制PHP框架之设计模式

class MySQL extends DB{
	private static $instance=null;
	public static function getInstance(){
		if(self::$instance==null){
			self::$instance=new MySQL();
		}
		return self::$instance;
	}
	public function MySQL(){
		
		/*Config*/
		$this->IP='*';
		$this->ServerID='*';
		$this->ServerPassword='*';
		$this->DataBaseName='*';
		/*End of Config*/
		
		$this->connection=mysqli_connect($this->IP,$this->ServerID,$this->ServerPassword,$this->DataBaseName);
		
		if(!$this->connection){
			die('Could not connect'.$this->connection);
		}
		
		mysqli_query($this->connection,'set names utf8');
	}

	public function Execute($sql){
		return mysqli_query($this->connection,$sql);	
	}

	public function Query($sql){
		$result=mysqli_query($this->connection,$sql);
		$arr=array();
		while($row=mysqli_fetch_array($result)){
			$arr[]=$row;
		}
		return $arr;
	}
	public function Close(){
		mysqli_close($this->connection);
	}
}

$db=new MySQL();

$db=MySQL::getInstance();

class ServiceProvider{
	public function Write($arg){
		echo $arg;
	}
}

class Facade{
	public static function getInstance($classname,$args){
		return new $classname($args);
	}
	
	public static function getFacadeAccessor(){
		//
	}
	
	public static function __callstatic($method,$args){
		$instance=static::getInstance(static::getFacadeAccessor(),$args);
		return call_user_func_array(array($instance,$method),$args);
	}
}

class MyFacade extends Facade{
	public static function getFacadeAccessor(){
		return ServiceProvider::class;
	}
}