后台线程如何更新地图数据

<P>MapXtreme B/S程序中,后台线程如何更新地图数据？</P>

<P>后台线程运行时，页面的地图显示失败。后台线程的代码如下，望各位高手指点</P>
<P>  private void updateFeature()<BR>  {<BR>   while(1==1)<BR>   {</P>
<P>    i+=1 ;<BR>    try<BR>    {<BR>     if(MapInfo.Engine.Session.Current.MapFactory!=null) <BR>     {<BR>      MapInfo.Mapping.Map map = MapInfo.Engine.Session.Current.MapFactory[0] ;</P>
<P>      if(map == null) return ;<BR>   <BR>      string FacilityCode = "12345" ;<BR>      string LayerName = "layer1" ;<BR>      MapInfo.Data.IResultSetFeatureCollection fc = MapInfo.Engine.Session.Current.Catalog.Search(LayerName, MapInfo.Data.SearchInfoFactory.SearchWhere("obj_code =" + FacilityCode ));<BR>      if (fc.Count == 0) return ;<BR>      if (fc == null) return ;</P>
<P>      foreach(MapInfo.Data.Feature f in fc)<BR>      {<BR>       MapInfo.Styles.AreaStyle ass = (MapInfo.Styles.AreaStyle) f.Style ;<BR>       MapInfo.Styles.SimpleInterior simpleInterior = new MapInfo.Styles.SimpleInterior() ;<BR>       int k = i ;<BR>       if( k%2 == 0)<BR>       {<BR>        simpleInterior.ForeColor = Color.Blue ;<BR>       }<BR>       else <BR>       {<BR>        simpleInterior.ForeColor = Color.Red  ;<BR>       }</P>
<P>       ass.Interior = simpleInterior ; <BR>       <BR>       f.Update() ;       }<BR>     }<BR>    }<BR>    catch(Exception er)<BR>    {<BR>     string ss = er.Message.ToString() ;  <BR>    }<BR>   }<BR>  }<BR></P>