Extent- how is the extent of a map determined.

[xariaD]

How to determine the extent of map.
When myMap is loaded it's full extent is not defined or is null.

The map was created in ArcMap, do we have to set the extent of map during creation?

[DominiqueBroux]

map.Layers has a method GetFullExtent which is giving the full extent of the map.
This method is only valid after the layer collection has been initialized.
So you have to subscribe to the 'LayersInitialized' event.

Something like:

private void MyMap_Initialized(object sender, System.EventArgs e)
{
 Map map = sender as Map;
 map.Layers.LayersInitialized += new LayerCollection.LayersInitializedHandler(Layers_LayersInitialized);
}

void Layers_LayersInitialized(object sender, System.EventArgs args)
{
 LayerCollection col = sender as LayerCollection;
 Envelope env = col.GetFullExtent();
}

[xariaD]

thank you.