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LFileSettings::GetPreLoadFilters

#include "ltwrappr.h"

static L_SSIZE_T LFileSettings::GetPreLoadFilters(pszFilters, uSize, pnFixedFilters, pnCachedFilters)

L_TCHAR * pszFilters;	/* pointer to a character string to be updated with filters */
L_SIZE_T uSize;	/* size in bytes of pszFilters */
L_INT * pnFixedFilters;	/* pointer to a variable to be updated */
L_INT * pnCachedFilters;	/* pointer to a variable to be updated */

Retrieves the current preloaded filters list.

Parameter	Description
pszFilters	Pointer to a character string to be updated with the current preloaded filters list.
uSize	The size in bytes of the buffer pointed to by pszFilters.
pnFixedFilters	Pointer to a variable to be updated with the number of filters that should stay loaded in memory at all times. Pass NULL if it is not required.
pnCachedFilters	Pointer to a variable to be updated with the number of filters that should be loaded. Pass NULL if it is not required.

Returns

>=0	The size in bytes of the preloaded filters list.
< 0	An error occurred. Refer to Return Codes.

Comments

In case the current preloaded filters list should be changed, call this function before calling the LFileSettings::PreloadFilters function.

The preload filters list contains the list of fixed and cached filters. For more information, refer to LFileSettings::PreloadFilters.

To retrieve the preloaded filters list, the user should:

1.	Call the function passing pszFilters as NULL and uSize as 0 to retrieve the size required for the filters list as returned value.
2.	Allocate a buffer of size (Returned Value * sizeof(L_TCHAR)).
3.	Call the function passing the allocated buffer to the pszFilters and the returned value to uSize to retrieve the filters list.

Required DLLs and Libraries

LTFIL For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

See Also

Functions:	LFileSettings::PreLoadFilters, LFileSettings::IgnoreFilters, LFileSettings::GetIgnoreFilters, Class Members
Topics:	Raster Image Functions: Input/Output File Filters
	Loading File Filters

Example

L_INT LFileSettings__GetPreLoadFiltersExample()
{
   L_TCHAR * pszList = NULL;
   L_INT nFixed;
   L_INT nCached;
   L_SIZE_T nRet;
   LBitmap Bitmap;
   L_TCHAR buf[80];
   /* get the original filters list */
   nRet = LFileSettings::GetPreLoadFilters(NULL, 0, NULL, NULL);
   pszList = (L_TCHAR *)malloc(nRet*sizeof(L_TCHAR));
   nRet = LFileSettings::GetPreLoadFilters(pszList, nRet, &nFixed, &nCached);
   ::MessageBox(NULL, pszList, TEXT("TEST"), MB_OK);
   free(pszList);
   wsprintf(buf, TEXT("fixed: %ld, cached: %ld"), nFixed, nCached);
   ::MessageBox(NULL, buf, TEXT("TEST"), MB_OK);
   /* change the preload filters */
   /* This example preloads the TGA, PCX and TIF filters */
   /* and allows 1 filter to be cached, while always    */
   /* keeping 2 loaded.                                 */
   LFileSettings::PreLoadFilters( 2, 1, TEXT("TGA,PCX,TIF"));
   /* get the new filters list */
   nRet = LFileSettings::GetPreLoadFilters(NULL, 0, NULL, NULL);
   pszList = (L_TCHAR *)malloc(nRet*sizeof(L_TCHAR));
   nRet = LFileSettings::GetPreLoadFilters(pszList, nRet, &nFixed, &nCached);
   ::MessageBox(NULL, pszList, TEXT("TEST"), MB_OK);
   free(pszList);
   wsprintf(buf, TEXT("fixed: %ld, cached: %ld"), nFixed, nCached);
   ::MessageBox(NULL, buf, TEXT("TEST"), MB_OK);
   /* try to load TGA */
   nRet = Bitmap.Load(TEXT("d:\\temp\\test.tga"));
   if(nRet == SUCCESS)
      ::MessageBox(NULL, TEXT("TGA loaded"), TEXT("TEST"), MB_OK);
}