As mentioned previously in Create Fields from an External Class, OpenROAD supports ActiveX Automation servers and ActiveX controls by treating these components and controls as external classes. An external class provides a named object definition that describes an external object, so that OpenROAD can use it seamlessly.

For example, it allows a spreadsheet, word processor, or other application to be used within an OpenROAD application. It also permits the inclusion of individual external controls—such as charts, grid controls, HTML controls, and web browsers—within an application. OpenROAD provides a container for the external object so that only its functionality is used. For, example, OpenROAD can read data from an external object, such as a Microsoft Excel spreadsheet, and use it in OpenROAD code.

Before you can use an external class in OpenROAD, you must register an external class library component with your application. Then you can declare and use external class objects and view their attributes and methods using the Class Browser. Registration means that OpenROAD wrapper code has been generated for an external object's exported attributes, methods, and events.