IAccessible::get_accHelpTopic
The IAccessible::get_accHelpTopic method retrieves the full path of the WinHelp file associated with the specified object and the identifier of the appropriate topic within that file. Not all objects support this property.
HRESULT get_accHelpTopic(
BSTR* pszHelpFile,VARIANTvarChild,long* pidTopic);
Parameters
- pszHelpFile
[out] Address of a BSTR that receives the full path of the WinHelp file associated with the specified object. - varChild
[in] Specifies whether the Help topic retrieved is that of the object or of one of the object's child elements. This parameter is either CHILDID_SELF (to obtain a Help topic for the object) or a child ID (to obtain a Help topic for one of the object's child elements). For more information about initializing the VARIANT structure, see How Child IDs Are Used in Parameters. - pidTopic
[out, retval] Address of a variable that identifies the Help file topic associated with the specified object. This value is used as the context identifier of the desired topic that passes to the Microsoft Win32 function WinHelp. When calling WinHelp to display the topic, set the uCommand parameter to HELP_CONTEXT, and cast the value pointed to by pidTopic to a DWORD and pass it as the dwData parameter.
Return Values
If successful, returns S_OK.
If not successful, returns one of the following values or another standard COM error code. Although servers return these values, clients must always check output parameters to ensure that they contain valid values. For more information, see Checking IAccessible Return Values.
| Error | Description |
|---|---|
| S_FALSE | No Help information is available. |
| E_INVALIDARG | An argument is invalid. |
| DISP_E_MEMBERNOTFOUND | The object does not support this property. |
Remarks
Getting information from a Help file might be time and memory intensive.
Note to server developers This property provides access to a Help topic in WinHelp, whereas IAccessible::get_accHelp returns a string. Objects are not required to support both IAccessible::get_accHelp and IAccessible::get_accHelpTopic, but they must support at least one. If they can easily return a string, they must support IAccessible::get_accHelp; otherwise they must support IAccessible::get_accHelpTopic. If both are supported, IAccessible::get_accHelpTopic provides more detailed information.
Requirements
** Windows NT/2000/XP/Server 2003:** Included in Windows 2000 and later.
** Windows 95/98/Me:** Included in Windows 98 and later.
** Redistributable:** Requires Active Accessibility 1.3 RDK on Windows NT 4.0 SP6 and Windows 95.
** Header:** Declared in Oleacc.h.
** Library:** Use Oleacc.lib.