silverlight中调用wcf方法的有关问题

silverlight中调用wcf方法的问题
人家写的方法：YCServiceClient client = new YCServiceClient();
                SLUtil.SetServiceAddress(client.Endpoint);

                client.GetWariningListCompleted += new EventHandler<GetWariningListCompletedEventArgs>(GetWariningListCompleted);


 void GetWariningListCompleted(object sender, GetWariningListCompletedEventArgs e)
        {
            //Dispatcher.BeginInvoke(() =>
            //{
            try
            {
                MapPage.ShowDebug("告警查询服务器耗时:" + (DateTime.Now - _warnLoadBegin).TotalSeconds + "秒");

                if (e.Error != null)
                {
                    ShowDebug(e.Error.Message + "\n" + e.Error.StackTrace);
                    return;
                }

                _warnList.Clear();
                alarmList.WarnList.ItemsSource = e.Result;
                //WarnList.ItemsSource = e.Result;

                if (e.Result.Count == 0)
                {
                    alarmList.WarnList.Visibility = System.Windows.Visibility.Collapsed;
                    alarmList.NoWarnInfo.Visibility = System.Windows.Visibility.Visible;
                }
                else
                {
                    alarmList.WarnList.Visibility = System.Windows.Visibility.Visible;
                    alarmList.NoWarnInfo.Visibility = System.Windows.Visibility.Collapsed;
                }

                if (WarnLayer == null)
                    return;

                WarnLayer.ClearStation(STA_WARN);
                foreach (WarnInfo info in e.Result)
                {
                    _warnList.Add(info.StId, info);
                    WarnLayer.AddStation(STA_WARN, info.StId, info.Jd, info.Wd, info);
                }

                audio.Stop();
                if (WarnLayer.Graphics.Count > 0)
                {
                    audio.Play();
                }
            }
            catch (Exception ex)
            {
                ShowDebug(ex.Message + "\n" + ex.StackTrace);
            }

            finally
            {
                CloseLoading();
                MapPage.ShowDebug(String.Format("告警加载开始时间:{0:HH:mm:ss}\n耗时：{1}秒", _warnLoadBegin, (DateTime.Now - _warnLoadBegin).TotalSeconds));
            }
            //});
        }


我也在wcf中定义了一个方法，但怎么才能写出类似这样的方法，是先写下面这个方法吗？下面方法参数类型GetWariningListCompletedEventArgs 是在哪儿定义的？
[解决办法]
GetWariningListCompletedEventArgs 应该是在服务端那边定义的，你上面的代码是silverlight（客户端）的代码。
[解决办法]
在解决方案的Web项目中添加“启用的Silverlight的WCF服务”，名称为Serivce1.svc
在Serivce1.svc中写上一个wcf服务后，在客户端项目引用该服务后就自动产生了:

     

[OperationContract]
        public List<T>  GetWariningListCompleted()
        {
           var q= from s in youTable ;
                
            return q.tolist();

        }

[OperationContract]
        public List<T>  GetWariningList()
        {
           var q= from s in youTable ;
                 
            return q.tolist();
 
        }