数组赋值的有关问题

数组赋值的问题

public function setParm($parameter, $value) {

		$this->parameter[$parameter] = $value;

		return $this;

	}


function geturl($type){

     $this->setproductparm($type);

     return $this->getData();

     }  

   

private function setproductparm($urltype){

     $this->parameter=array();

     $this->type="";

     $this->setParm("Marketplace",self::marketplaceId);

     $this->version="2009-01-01";

     switch ($urltype){

        case "RequestReport":    

            $this->setParm("Action","RequestReport");

            $this->setParm("ReportType","_GET_MERCHANT_LISTINGS_DATA_");

        break;

        case "GetReportList":  

            $this->setParm("Action","GetReportList");   

            $this->setParm("ReportRequestIdList.Id.1",$this->ReportRequestId);

        break;

        case "GetReport":  

            $this->setParm("Action","GetReport");   

            $this->setParm("ReportId",$this->ReportId);  

        break;   

          

              

        }

        

     }

$url1=$aa->geturl("RequestReport");
$url2=$aa->geturl("GetReportList");
$url3=$aa->geturl("GetReport");

我明明每次执行前都清除了数组
$this->parameter=array();
但输出时，每次数组都包含了上次所赋的值。
每次结果：
$url1：ReportType=_GET_MERCHANT_LISTINGS_DATA_
$url2：ReportType=_GET_MERCHANT_LISTINGS_DATA_&ReportRequestIdList.Id.1=123456
$url3：ReportType=_GET_MERCHANT_LISTINGS_DATA_&ReportRequestIdList.Id.1=123456&ReportId=123456

请问是哪里的问题啊？？？
------解决思路----------------------
你没有给出 getData 的定义，不好说
------解决思路----------------------

//看看是不是下面的方法哪里处理了

getData();