php调用webservice上传文件

function uploadFileToOA($file=array(),$senderLoginName)
{
    $client=new \SoapClient("http://XXX.XXX.XXX.XXX/xxx?wsdl");
    $param=array("userName"=>"用户名","password"=>"密码");
    $token = $client->__soapCall('authenticate',array($param));
    $PostUrl = "http://XXX.XXX.XXX.XXX/XXXLoginName."&token=".$token->return->id;
    $fields = array("file"=>$file);
    $curl = curl_init($PostUrl);
    curl_setopt($curl, CURLOPT_POST,true);
    curl_setopt($curl, CURLOPT_POSTFIELDS, $fields);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER,1);
    $result = curl_exec($curl);
    curl_close($curl);
    return $result;
}