PHP如何访问SOAP？

<?php 
/** 
* 实现业务逻辑的类，此类是一个普通类 
* 
*/ 
class test { 
       /** 
        * 返回一个字符串：Hello World! 
        * 
        * @return string 
        */ 
       public function returnString(){ 
               return "Hello World!"; 
       } 
       public function returnArray($array)
       {
            return array(
                            array('id'=>0,'name'=>'a'),
                            array('id'=>1,'name'=>'b'),
                            array('id'=>2,'name'=>'c'),
                            $array
                        );
       }
       public function sum($a,$b)
       {
               return $a+$b;
       }
} 
/** 
* 创建Server对象 
*/ 
$arrOptions = array('uri'=>'http://example.com/');    //设置命名空间 
$objSoapServer = new SoapServer(null,$arrOptions); 
/** 
* 注册Basic类的所有方法 
*/ 
$objSoapServer->setClass("test"); 
/** 
* 处理请求 
*/ 
$objSoapServer->handle(); 
?> 

<?php 
/** 
* Client端，首先创建Client对象 
*/ 
$arrOptions = array('uri'=>'http://example.com/',                     //设置命名空间 
                       'location'=>'http://localhost/test_/xmlrpc/server/server2.php',        //设置Server地址 
                       'trace'=>true); 
$objSoapClient = new SoapClient(null,$arrOptions); 
/** 
* 远程调用 
*/ 
echo "<pre/>";
//try{ 
//   $strReturn = $objSoapClient->returnString(); 
//}catch(Exception $e){ 
//} 
//echo $strReturn; 
$strReturn2 = $objSoapClient->returnArray(array('id'=>4,"name"=>"d")); 
print_r($strReturn2);
$strReturn3 = $objSoapClient->sum(3,4); 
print_r($strReturn3);
?>