'宣言 Protected MustOverride Sub GetTileLayers( _ ByVal tileLevel As Integer, _ ByVal tilePositionX As Integer, _ ByVal tilePositionY As Integer, _ ByVal tileImageLayerSources As IList(Of Object) _ )
protected abstract void GetTileLayers( int tileLevel, int tilePositionX, int tilePositionY, IList<object> tileImageLayerSources )