ining forms and VB code, and it invokes the plug-in container to interpret the form and code, handle database/server communications, and host any embedded OLE Controls (OCXes). The form springs to life inside a World Wide Web page.
Programmers use the Component Workbench to create Openscape forms. The Workbench is a clone of the VB desktop, and a programmer familiar with VB can immediately use the workbench to create .OPP files containing forms and VB code for downloading over the Web.
Openscape is designed to be a Web front end for an enterprise database system. Its run-time client uses remote procedure calls (RPCs) to communicate with database servers. Openscape is one of the first contestants in the race to create new lightweight database clients that can load into Web browsers to provide global database deployment.
At the W3 Consortium conference in De
cember, the company showed an alpha version of its Internet Explorer Web browser running as an OLE container. OCXes can be placed on an Internet Explorer Web page with the new Insert tag, provided that the corresponding OLE server is already installed on the client computer.
Microsoft also demonstrated at the conference a VBscript OCX that implements VB. Embedded on a Web page, the VBscript control runs a program that can respond to user events and control other OCX objects on the same page.
OCX embedding raises questions. How will the required OCX code arrive at the client computer? How will users verify that it comes from a trusted vendor? Will there be fast or automatic install and uninstall? What about non-Windows users? Microsoft claims to be working on digital-signature technology for approving OCX distributions, enhancements to the Windows OS for automatic installation and uninstallation, and portable or cross-compiled OCX technology.
screen_link (68 Kbytes)
Object Power's Openscape is a Visual Basic clone for building Web applications out of embedded OCXes.
OCX-Based Alternatives
