An OpenEdge application executes the Windows help engine (hh.exe or Winhlp32.exe) using the SYSTEM-HELP statement. Here is the syntax for the SYSTEM-HELP statement:
Syntax
SYSTEM-HELP file-string [ WINDOW-NAME window-name] { CONTENTS
| CONTEXT int-expr | HELP-TOPIC string | KEY string | ALTERNATE-KEY string | POSITION X x Y y WIDTH dx HEIGHT dy | POSITION MAXIMIZE
| QUIT
| SET-CONTENTS int-expr | CONTEXT-POPUP int-expr | PARTIAL-KEY string | MULTIPLE-KEY char TEXT string | COMMAND string | FINDER
| FORCE-FILE
| HELP
}
file-string
The file-string parameter is a character expression that specifies the pathname of a help file. If the file has a .chm extension (the extension for compiled Microsoft HTML Help files), the Microsoft HTML Help viewer is launched. If the file has a .hlp file extension, the Microsoft Windows Help viewer is launched.
WINDOW-NAME window-name
The window-name parameter is a character expression that evaluates to the primary or secondary window name as defined in the [WINDOWS] section of the help project file. If the window name is omitted, or if "main" is specified, the primary help window is used.
Note: This option is supported in Windows Help (.hlp files) only.
CONTENTS
For HTML Help, this option displays the Microsoft HTML Help viewer with the default topic in the content pane. Use the HELP-TOPIC option to specify the topic to display.
In Windows Help, this option displays the help topic defined as the contents in the [OPTIONS] section of the help project file.
Note: This option is supported for backward compatibility only.
CONTEXT int-expr
Displays the help topic that the context number identifies. You define context numbers in the [MAP] section of the help project file.
The int-expr parameter is the context number for the help topic.
HELP-TOPIC string
Displays a help topic in the content pane of the Microsoft HTML Help viewer.
The string parameter is a character expression that indicates the topic (.htm/.html file) within the compiled Microsoft HTML Help (.chm) file to display.
Note: This option is supported for HTML Help (.chm files) only.
KEY string
For HTML Help, this option displays the topic matching the string found in the keyword index. Use semicolons in the string parameter to delimit multiple keywords. If no match is found, Microsoft HTML Help displays the help viewer with the Index tab on top.
In Windows Help, this option displays the help topic matching the string found in the index keyword list. If there is more than one match, it displays the first topic containing the keyword. If there is no match or the string is omitted, a message is displayed indicating that the keyword is invalid. The string parameter is a character expression that evaluates to a keyword for the desired help topic.
ALTERNATE-KEY string
Displays a help topic matching the string found in the alternate keyword (Alink) index. The string parameter is a character expression that evaluates to a keyword in the alternate keyword index.
Note: This option is supported for HTML Help (.chm files) only. In Windows Help (.hlp files), see the MULTIPLE–KEY option.
POSITION X x Y y WIDTH dx HEIGHT dy
Positions an existing (already opened) help window as specified.
The x parameter is an integer expression that specifies the x coordinate for the help window.
The y parameter is an integer expression that specifies the y coordinate for the help window.
The dx parameter is an integer expression that specifies the width of the help window.
The dy parameter is an integer expression that specifies the height of the help window.
POSITION MAXIMIZE
Maximizes an existing (already opened) help window.
QUIT
Informs the help application that help is no longer required. If no other applications are using help, the operating system closes the help application.
SET-CONTENTS int-expr
Dynamically remaps the contents help topic from what is defined in the [OPTIONS] section of the help project file. When a CONTENTS call is made, the new contents help topic is displayed.
The int-expr parameter is the context number for the new contents help topic.
Note: This option is supported in Windows Help (.hlp files) only. This option is supported for backward compatibility only.
CONTEXT-POPUP int-expr
Displays the help topic in a pop-up window that the context number identifies. You define context numbers in the [MAP] section of the help project file. If a nonscrolling region exists in a help topic, only that region displays when you use the CONTEXT-POPUP option to display the topic.
The int-expr parameter is the context number for the help topic.
Note: This option is supported in Windows Help (.hlp files) only.
PARTIAL-KEY string
Displays the help topic matching the string found in the keyword list. In Windows, if there is more than one match, no match, or if the string is omitted, it displays the Help Topics: Window Help Topics dialog box with the Index tab on top.
The string parameter is a character expression that evaluates to a partial key for the desired help topic.
Note: This option is supported in Windows Help (.hlp files) only.
MULTIPLE-KEY char TEXT string
Displays the help topic matching a keyword from an alternate keyword table.
The char parameter is a character expression that evaluates to the single character keyword table identifier for the required table.
The string parameter is a character expression that evaluates to the keyword that is located in the keyword table.
Note: This option is supported in Windows Help (.hlp files) only. For HTML Help, see the ALTERNATE-KEY option.
COMMAND string
Executes a help macro.
The string parameter is a character expression that evaluates to the help macro to execute.
Note: This option is supported in Windows Help (.hlp files) only.
FINDER
Displays the Help Topics: Windows Help Topics dialog box, which contains an Index tab, a Find tab, and optionally a Contents tab, with the most recently used tab displayed on top.
If a Contents tab file (.cnt file) is present when you initially call the Help Topics: Windows Help dialog box, then the Contents tab displays on top. However, if a.cnt file is not present, then the dialog box displays with the Index tab on top; the Contents tab is not available.
Note: This option is supported in Windows Help (.hlp files) only.
FORCE-FILE
Ensures that the correct help file is open and displayed.
Note: This option is supported in Windows Help (.hlp files) only.
HELP
Displays the contents of the OpenEdge Help-on-Help file. In Windows, HELP displays the Help Topics: Windows Help Topics dialog box.
Note: This option is supported in Windows Help (.hlp files) only.