ArcGISDynamicMapServiceLayer.FullExtent is Null

Question

i am trying to add a dynamic map service layer, and zoom to that layer, but the full-extent of the layer it is always null...

ArcGISDynamicMapServiceLayer mylayer = new ArcGISDynamicMapServiceLayer();
                mylayer.DisableClientCaching = true;//recommended 
                mylayer.Url = DynamicUrl ;
                mylayer.ID = "CURRENTLAYER";

int totlayers = this.MyMap1.Layers.Count;
                this.MyMap1.Layers.Insert(totlayers, mylayer);
                 
                Envelope anenv = mylayer.FullExtent;
                 MyMap1.ZoomTo(anenv);
//anenv is always null

how do i handle that?

thanks a lot

DominiqueBroux · Answer

You can find a sample of what Andrew mentioned here.

You have to wire up the 'ZoomToFullExtent' handler to the  'Initialized' layer event. 
The handler projects the fullextent to the map spatial reference coordinates (using a geometry service if needed).

deleted-user-ATjHIWsdQYmT · Answer

You can use a GeometryService to project your envelope from your layer's spatial reference to 102100.  Here's the API documentation with example:
http://resources.arcgis.com/en/help/silverlight-api/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.Tasks.GeometryService~ProjectAsync(IEnumerable{Graphic},SpatialReference).html

Note the input has to be a graphic so you can just create a new graphic using the extent of your envelope.  You'll raise a "ProjectCompleted" event.  From there you can take the result and use that to zoom to your layer extent.  That'll work.

AshakaThakore · Answer

I'd probably do it after you insert it into your map.  Are you trying to insert the layer at a specific place in your layer order?  Otherwise you can just use MyMap.Add(mylayer);

Yes, i am trying to insert at particular location

here on this link i found that i should insert after initialize is done

http://forums.arcgis.com/threads/59382-Layer-not-initialized?highlight=arcgis+layer+initialize%28%29

So It did work...

now the problem is i want to zoom to that layer after its initialized and my my map's SRID is 102100
And my layer's projection/SRID is different and if i do - mymap.zoomto(mylayer.fullextent) it zooms to wrong place bcos SRID are different

pl help

how should i project that fullextent to srid 102100 or how should i handle this problem

thanks a lot