DdfInform
This function defines a hypertext inform link, which sends an HM_INFORM message to the application with a res= attribute. It also corresponds to the link tag with reftype=inform.
Syntax
DdfInform(hddf, pszText, resInformNumber)
Parameters
- hddf (HDDF) - input
- Handle to DDF returned by DdfInitialize.
- pszText (PCSZ) - input
- Hypertext phrase.
- resInformNumber (ULONG) - input
- Res number associated with this hypertext field.
- Possible values are 1 to 64000; all other values are reserved.
Returns
- rc (BOOL) - returns
- Success indicator.
- TRUE: Successful completion.
- FALSE: Error occurred.
Errors
Possible returns from WinGetLastError:
- HMERR_DDF_MEMORY (0x3001): Not enough memory is available.
Example Code
Declare:
#define INCL_DDF #include <os2.h> HDDF hddf; /* Handle to DDF returned by DdfInitialize. */ PCSZ pszText; /* Hypertext phrase. */ ULONG resInformNumber; /* Res number associated with this hypertext field. */ BOOL rc; /* Success indicator. */ rc = DdfInform(hddf, pszText, resInformNumber);
After initializing a DDF buffer with DdfInitialize, the example uses DdfInform to create a hypertext inform link with another resource (corresponds to the IPF :link. tag with reftype=inform). For a more detailed example and discussion of initializing DDF, see the DdfInitialize sample.
#define INCL_WINWINDOWMGR /* General window management */
#define INCL_WINMESSAGEMGR /* Message management */
#define INCL_DDF /* Dynamic Data Facility */
#include <os2.h>
#include <pmhelp.h>
PSZ Text = "This text is a HYPERTEXT message.\n"; /* hypertext string */
MRESULT WindowProc( HWND hwnd, ULONG ulMsg, MPARAM mp1, MPARAM mp2 )
{
HWND hwndParent;
HWND hwndInstance;
HDDF hDdf; /* DDF handle */
switch( ulMsg )
{
case HM_QUERY_DDF_DATA:
/* get the help instance */
hwndParent = WinQueryWindow( hwnd, QW_PARENT );
hwndParent = WinQueryWindow( hwndParent, QW_PARENT );
hwndInstance = (HWND)WinSendMsg( hwndParent, HM_QUERY,
MPFROMSHORT( HMQW_INSTANCE ), NULL );
/* Allocate 1K Buffer (default) */
hDdf = DdfInitialize(
hwndInstance, /* Handle of help instance */
0L, /* Default buffer size */
0L /* Default increment */
);
if (hDdf == NULLHANDLE) /* Check return code */
{
return (MRESULT)FALSE;
}
/* create hypertext inform link with resource 1 */
if (!DdfInform(hDdf, (PSZ)Text, 1L))
{
return (MRESULT)FALSE;
}
return (MRESULT)hDdf;
}
return WinDefWindowProc(hwnd, ulMsg, mp1, mp2); /* Default processing for other messages */
}