Public Function BeginDownload( _
   ByVal FIDs As FIDSet, _
   ByVal Geometry As Geometry, _
   ByVal Format As String, _
   ByVal callback As AsyncCallback, _
   ByVal asyncState As Object _
) As IAsyncResult

Dim instance As ImageServerProxy
Dim FIDs As FIDSet
Dim Geometry As Geometry
Dim Format As String
Dim callback As AsyncCallback
Dim asyncState As Object
Dim value As IAsyncResult
 
value = instance.BeginDownload(FIDs, Geometry, Format, callback, asyncState)

public IAsyncResult BeginDownload( 
   FIDSet FIDs,
   Geometry Geometry,
   string Format,
   AsyncCallback callback,
   object asyncState
)