Extent is zooming map to 0,0 in ArcGIS API for Silverlight?

Question

When I use this code (from the example):

        ESRI.ArcGIS.Client.Geometry.Envelope myEnvelope = new ESRI.ArcGIS.Client.Geometry.Envelope();
        myEnvelope.XMin = -130;
        myEnvelope.YMin = 5;
        myEnvelope.XMax = -70;
        myEnvelope.YMax = 65;
        mapControl.Extent = myEnvelope;

The map is centered over that ever-popular and fascinating point off the coast of Africa: 0,0.

What am I doing wrong?

Answer 1

What's the coordinate system aka spatial reference of the map? If it's 3857 / Web Mercator, these lat/lon values are probably being interpreted as xy values in meters. You may need to project the envelope or the points before creating the envelope. First, you might try assigning a geographic coordinate system to the envelope but I don't know if it will work.