WinHelp
The WinHelp
function starts Windows Help (WINHELP.EXE) and passes additional data
indicating the nature of the help requested by the application. The application
specifies the name and, where required, the directory path of the help file to
display.
BOOL WinHelp(
|
HWND
hWndMain, |
// handle of window
requesting Help |
|
LPCTSTR lpszHelp, |
// address of
directory-path string |
|
UINT uCommand, |
// type of Help |
|
DWORD dwData |
// additional data |
|
); |
|
Parameters
hWndMain
Identifies
the window requesting Help. The WinHelp function uses this handle to
keep track of which applications have requested Help.
lpszHelp
Points to a
null-terminated string containing the path, if necessary, and the name of the
Help file that the Help application is to display.
The filename
may be followed by an angle bracket (>) and the name of a secondary window
if the topic is to be displayed in a secondary window rather than in the
primary window. The name of the secondary window must have been defined in the
[WINDOWS] section of the Help project (.HPJ) file.
uCommand
Specifies the
type of help requested. For a list of possible values and how they affect the
value to place in the dwData parameter, see the Remarks section.
dwData
Specifies
additional data. The value used depends on the value of the uCommand
parameter. For a list of possible values, see the Remarks section.
Return Values
If the
function succeeds, the return value is nonzero.
If the
function fails, the return value is zero.
Remarks
Before
closing the window that requested Help, the application must call WinHelp
with the uCommand parameter set to HELP_QUIT. Until all applications
have done this, Windows Help will not terminate. Note that calling WinHelp with
the HELP_QUIT command is not necessary if you used the HELP_CONTEXTPOPUP
command to start Help
The following
table shows the possible values for the uCommand parameter and the
corresponding formats of the dwData parameter:
|
uCommand |
Action |
dwData |
|
HELP_COMMAND |
Executes a
Help macro or macro string. |
Address of
a string that specifies the name of the Help macro(s) to execute. If the
string specifies multiple macros names, the names must be separated by
semicolons. You must use the short form of the macro name for some macros
because Help does not support the long name. |
|
HELP_CONTENTS |
Displays
the topic specified by the Contents option in the [OPTIONS] section of the
.HPJ file. This is for backward compatibility. New applications should
provide a .CNT file and use the HELP_FINDER command. |
Ignored,
set to 0. |
|
HELP_CONTEXT |
Displays
the topic identified by the specified context identifier defined in the [MAP]
section of the .HPJ file. |
Unsigned
long integer containing the context identifier for the topic. |
|
HELP_CONTEXTPOPUP |
Displays,
in a pop-up window, the topic identified by the specified context identifier
defined in the [MAP] section of the .HPJ file. |
Unsigned
long integer containing the context identifier for a topic. |
|
HELP_FORCEFILE |
Ensures
that WinHelp is displaying the correct help file. If the incorrect
help file is being displayed, WinHelp opens the correct one;
otherwise, there is no action. |
Ignored,
set to 0. |
|
HELP_HELPONHELP |
Displays
help on how to use Windows Help, if the WINHELP.HLP file is available. |
Ignored,
set to 0. |
|
HELP_INDEX |
Displays
the Index in the Help Topics dialog box. This command is for backward
compatibility. New applications should use the HELP_FINDER command. |
Ignored,
set to 0. |
|
HELP_KEY |
Displays
the topic in the keyword table that matches the specified keyword, if there
is an exact match. If there is more than one match, displays the Index with
the topics listed in the Topics Found list box. |
Address of
a keyword string. |
|
HELP_MULTIKEY |
Displays
the topic specified by a keyword in an alternative keyword table. |
Address of
a MULTIKEYHELP
structure that specifies a table footnote character and a keyword. |
|
HELP_PARTIALKEY |
Displays
the topic in the keyword table that matches the specified keyword, if there
is an exact match. If there is more than one match, displays the Index tab.
To display the Index without passing a keyword (the third result), you should
use a pointer to an empty string. |
Address of
a keyword string. |
|
HELP_QUIT |
Informs the
Help application that it is no longer needed. If no other applications have
asked for Help, Windows closes the Help application. |
Ignored,
set to 0. |
|
HELP_SETCONTENTS |
Specifies
the Contents topic. The Help application displays this topic when the user
clicks the Contents button. |
Unsigned
long integer containing the context identifier for the Contents topic. |
|
HELP_SETINDEX |
Specifies a
keyword table to be displayed in the Index of the Help Topics dialog box. |
Unsigned
long integer containing the context identifier for the Index topic. |
|
HELP_SETWINPOS |
Displays
the Help window, if it is minimized or in memory, and sets its size and
position as specified. |
Address of
a HELPWININFO
structure that specifies the size and position of either a primary or
secondary Help window. |
See Also