按月份分组数据

	/*************************
	 * author:wangwang
	 * date:2011.3.16
	 * func:按月份分组数据
	 * pma:$month=array('2011-1') 
		$dataList=array(
			array('aa'=>'aa','recharge_date'=>'2011-1'),
			array('aa'=>'aa','recharge_date'=>'2011-1')
		);
	*/
	public function getDataByMonth($month,$dataList){
		if(!empty($dataList)){
			foreach($dataList as $row){
				$rowMonth = substr($row['recharge_date'],0,7);  
				if(in_array($rowMonth,$month)){
					$data[$rowMonth][]=$row;
				}
			}
		}
		return $data;
	}