Accessing the API
The functionality provided by HTML Help is located inside a dynamic link library named hhctrl.ocx. Besides hosting the HTML Help Active X control this library also exports the HtmlHelpA and HtmlHelpW functions. To use the HTML Help API you have to link against this DLL. If you use implicit linking (the default for the interface unit) then you must make sure that the hhctrl.ocx is installed on the target system and can be found by the Windows loader. When using the explicit linking option you also have to make sure this file is present on the target system and that it is registered. Once registered the LoadHtmlHelp function will be able to find it. The hhctrl.ocx file is installed and registered automatically by HTML Help Workshop as well as by hhupd.exe, both of which can be downloaded from the Microsoft website.
About HtmlHlp.pas
HtmlHlp.pas is the Pascal interface unit which allows you to call the HtmlHelp
function. This file is a complete translation of the original htmlhelp.h header file
distributed with HTML Help Workshop 1.21. To use HTML Help in your applications you must
include this file in your uses section and make sure it can be found by the compiler, by
placing it somewhere on the search path. This file is located in the Pas subfolder of the
HtmlHelp.zip file.
Notes:
If you are using the HTML Help API with Windows 95 and Internet Explorer 3.x,
you must either set up DCOM for Microsoft Windows® 95, version 1.2, or set up Internet Explorer 4.x.
Otherwise, the calls that you make to HtmlHelp() may not be processed correctly.