About ActiveX Technology
Sterling Gentran:Server® supports additional extended rule functionality to allow you to use Microsoft’s ActiveX Data Objects (ADO) from within extended rules, as well as providing enhancements to user exit support.
The information in the following topics assumes that you:
- Are familiar with the use of ActiveX Automation Servers and languages such as C++.
- Know the Translator Programming Language (TPL) constructs for creating, manipulating, and deleting ActiveX objects.
- Know the ProgID of the ActiveX object and all its exposed interfaces.
- Understand how and when extended rules are invoked and their scope.
User exits are an advanced feature of Sterling Gentran:Server that should only be used with the above prerequisites.
Restrictions
Sterling Gentran:Server extended rules selectively support ActiveX technology.
Sterling Gentran:Server extended rules support:
- ActiveX Automation Servers
- Some ActiveX Controls, but only those that work as Automation Servers
Sterling Gentran:Server does not support:
- ActiveX controls that are not ActiveX Automation Servers. Such ActiveX controls must be hosted in a graphical user interface (GUI) display, and therefore cannot be used from extended rules
- ActiveX Arrays (for example, the VT_ARRAY data type modifier)
- References (for example, the VT_BYREF data type modifier) except for output parameters in method calls. In this instance, references are only valid for the duration of the method call.
- Sterling Gentran:Server does not read registry entries or type libraries when compiling extended rules to verify the accuracy of programmatic identifiers (ProgIDs) or interfaces.
- Extended rules that compare two ActiveX properties or method results, or any combination of properties or method results. This type of comparison is invalid because property and method types are unknown prior to compilation and thus it is not possible to generate the correct comparison code.
Definition of ActiveX Terminology
ActiveX is a term that encompasses a set of rules that define how applications should share information. ActiveX grew out of technologies developed by Microsoft, specifically Object Linking and Embedding (OLE) and Component Object Model (COM).
An ActiveX automation server is an ActiveX component (a .DLL or .EXE program) that can expose part of its functionality, specifically properties and methods, via the IDispatch interface to another program on the system.
Some ActiveX controls function as automation servers.
The IDispatch interface is a standard COM interface. Automation Servers typically expose their methods and properties through this interface.
A method is an action or function that is performed by an object (for example, a calculation or a search).
A property is a characteristic or parameter of an object (for example, type, size, or creation date).
ActiveX controls are a specifically defined method of implementing ActiveX technologies. Basically an ActiveX control is a software component that executes common tasks and can integrate into the user interface of an application that provides the necessary ActiveX control host functionality.
The ActiveX control specification enables you to build component software that interacts with your application and Sterling Gentran:Server. ActiveX controls require a user interface, so they are not appropriate for translation user exits. These controls can be developed in a variety of programming languages, including C++.