Public Function BeginUnion( _
   ByVal SpatialReference As SpatialReference, _
   ByVal InGeometryArray() As Geometry, _
   ByVal callback As AsyncCallback, _
   ByVal asyncState As Object _
) As IAsyncResult

Dim instance As GeometryServerProxy
Dim SpatialReference As SpatialReference
Dim InGeometryArray() As Geometry
Dim callback As AsyncCallback
Dim asyncState As Object
Dim value As IAsyncResult
 
value = instance.BeginUnion(SpatialReference, InGeometryArray, callback, asyncState)

public IAsyncResult BeginUnion( 
   SpatialReference SpatialReference,
   Geometry[] InGeometryArray,
   AsyncCallback callback,
   object asyncState
)