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Reprojecting a Point

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2
10-21-2011 06:00 AM
AaronNash
Deactivated User
I have been struggling with this code for a few days now and have not come to a resolution. What I am trying to do is reproject a geolocation event to display on a base map in a state plane projection. I would prefer to do the calculation on the client side but since I do not know the formula to go from WGS84 to CT State plane NAD83, I am stuck sending the request to my geometry service. I have tried almost everything I can think of (thats why I am posting), in debugging mode I can see the values (Lat and Long) being passed to the geometry service with the output spatial reference, but there are no values being returned. I have tried the ESRI geometry service and my own (which is server 9.3.1), but return no results.
   private function onTravel(event:GeolocationEvent):void 
   { 
     var long:String = event.longitude.toString();
     var lat:String = event.latitude.toString();
     var longnew:Number = Number(long);
     var latnew:Number = Number(lat);
     var GPSPoint:MapPoint = new MapPoint(longnew, latnew);
     geoLat.text = event.latitude.toString();
     geoLong.text = event.longitude.toString(); 
     var graphic:Graphic = new Graphic(GPSPoint, GPSicon);      
     myGraphicsLayer.clear(); 
     myGraphicsLayer.add(graphic);
     var outSR:SpatialReference = new SpatialReference(2234);    
     geometryService.project([GPSPoint as Geometry], outSR); 

   }  


   private function projectCompleteHandler(event:GeometryServiceEvent):void
   { 
    try
    {
  
   
    var pt:MapPoint = (event.result as Array)[0]as MapPoint;
    reprojectLat.text = pt.x.toString();
    reprojectLong.text = pt.y.toString();
    }
    catch (error:Error)
    {
     Alert.show(error.toString());
    }
   }


Here is the code I am using, instead of reprojecting the data to display on the map. I created a box on the map that would show the current X and Y and the reprojected X and Y, the map service I am using is in WGS 1984 and the GPS mappoint is displayed correctly on the map. I just cannot figure out why the geometry service is not returning any values...HELP

thanks,
Aaron
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2 Replies
RobertScheitlin__GISP
MVP Emeritus
Aaron,

   You need to specify the Spatial Reference of the GPSPoint before you send it to the geometry service for projection (i.e. 4326 if it is WGS 1984).
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AaronNash
Deactivated User
that was it, like always thanks so so much for your help. I am now finally returning values
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