我正在使用Silverlight 5
并WCF data service
安装了 Silverlight WCF 数据服务客户端库。
理想情况下,当我执行时DataServiceQuery<T>.BeginExecute
,回调应该在工作线程上返回,但在我的情况下,它会在 UI 线程上返回。
为什么我担心的是我的有效载荷非常大,需要大约 6-7 秒才能实现对对象的响应(DataServiceQuery<T>.EndExecute method
)。因此,如果它在 UI 线程上运行,它会阻塞我的 UI 6-7 秒。
如何在工作线程上获得响应,在工作线程上实现响应,然后切换到 UI 线程来更新我的 UI。
有没有人遇到过类似的问题?
这是我的代码。
private void getRealTimeAssetProfileQuery(Guid assetProfileID, DateTime fromDate, DateTime toDate)
{
dateRanges[assetProfileID].Add(new Range<DateTime>(fromDate, toDate));
context = ServiceAgent.Context;
var qry = (from o in context.RealTimeProfilePoint
where o.ProfileID == assetProfileID && o.PointTime >= fromDate && o.PointTime <= toDate
orderby o.PointTime descending
select o) as DataServiceQuery<RealTimeProfilePoint>;
qry = qry.AddQueryOption("$expand", "Profile");
qry = qry.AddQueryOption("$expand", "Profile/ProfileType");
dynamic asyncState = new
{
assetProfileID = assetProfileID,
fromDate = fromDate,
toDate = toDate
};
Uri qryUri = new Uri(qry.ToString());
context.BeginExecute<RealTimeProfilePoint>(qryUri, new AsyncCallback(realTimeCallBack), asyncState);
}
void realTimeCallBack(IAsyncResult asyncResult)
{
if (Deployment.Current.Dispatcher.CheckAccess())
raiseTrace("Data Service Response On UI Thread \n");
else
raiseTrace("Data Service Response On worker Thread \n");
dynamic asyncState = asyncResult.AsyncState as dynamic;
Guid assetProfileID = asyncState.assetProfileID;
DateTime fromDate = asyncState.fromDate;
DateTime toDate = asyncState.toDate;
IEnumerable<RealTimeProfilePoint> profilePoints = context.EndExecute<RealTimeProfilePoint>(asyncResult);
List<RealTimeProfilePoint> lstProfilePoint = profilePoints.ToList();
if (((QueryOperationResponse)profilePoints).GetContinuation() != null)
{
Uri qryUri = ((QueryOperationResponse)profilePoints).GetContinuation().NextLinkUri;
context.BeginExecute<RealTimeProfilePoint>(qryUri, new AsyncCallback(realTimeCallBack), asyncState);
}
if (lstProfilePoint.Count > 0)
{
var assetProfile = lstProfilePoint[0].Profile;
Instance.addRealTimePoints(assetProfile, lstProfilePoint);
raiseTrace(
"Fetching Real Time Profile Points from Server for AssetProfileID " +
assetProfileID.ToString() + " : " +
lstProfilePoint.Count.ToString() + " record(s) found for" +
fromDate.ToUtcTime().ToString() + " - " + toDate.ToUtcTime().ToString() +
" peiod.");
}
}