如何从android中的webservice获取sessionid？

Question

function Login($Email, $Password) {
    global $DBConnection;
    if ((isset($UserName) && !empty($UserName)) || (isset($Password) && !empty($Password))) {
        $Email = addslashes(htmlspecialchars(strip_tags($Email)));
        if ($DBConnection->row("select * from db_Users where Users_Email = '".$Email."' and Users_Password = '".$Password."'") <= 0) {
            return "FAILED";
        }
        else {
            $UserLogin = $DBConnection->object("select * from db_Users where Users_Email = '".$Email."' and Users_Password = '".$Password."'");
            $_SESSION['UserLogin'] = true;
            $_SESSION['UserID'] = $UserLogin->Users_ID;
            return "SUCCESS";
        }
    }
    else {
        return "ERROR";
    }
}

我的功能是这个在webservice部分..我需要获取sessionid ..我使用soapobject.I不知道该怎么办。任何建议？提前谢谢你......