L_TwainGetCapabilityFromFile

Show in webframe

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainGetCapabilityFromFile (hSession, hFile, ppCapability, uIndex)

HTWAINSESSION hSession;	/* handle to an existing TWAIN session */
HTWAINTEMPLATEFILE hFile;	/* handle to an existing template file */
pTW_CAPABILITY * ppCapability;	/* pointer to a pointer to a structure */
L_UINT uIndex;	/* capability index */

Gets the capability, at the specified index, in the specified file.

Parameter	Description
hSession	Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession function.
hFile	Handle to an existing template file.
ppCapability	Pointer to a pointer to a TW_CAPABILITY structure. This structure will be allocated internally.
uIndex	Index of the capability to get from the file. This is a zero-based index.

Returns

SUCCESS	The function was successful.
! = SUCCESS	An error occurred. Refer to Return Codes.

Comments

To get a capability stored in a file; the file must be opened for reading by calling L_TwainOpenTemplateFile function. The user must declare a variable of type pTW_CAPABILITY and pass the address of this to the function. This parameter will be updated with a pointer to the capability at the specified index.

Note:

If the function is successful, the user must:

Free the container of the TW_CAPABILITY structure by a calling L_TwainFreeContainer function.
Free the value referenced by the contents of the ppCapability using GlobalUnlock and GlobalFree.

Required DLLs and Libraries

LTTWN

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

See Also

Functions:	L_TwainOpenTemplateFile, L_TwainAddCapabilityToFile, L_TwainTemplateDlg, L_TwainGetNumOfCapsInFile, L_TwainCloseTemplateFile, L_TwainInitSession, L_TwainEndSession.
Topics:	Handling Template Files
	TWAIN Functionality: Capability Functions.

Example

L_INT  TwainGetCapabilityFromFileExample(HTWAINTEMPLATEFILE hFile,
                                                         HWND               hDlg, // Parent dialog handle
                                                         HTWAINSESSION g_hSession)
{
   L_INT nRet;
   OPENFILENAME ofn;
   L_TCHAR szFilePath[MAX_PATH];

   memset (&ofn, 0, sizeof(OPENFILENAME));
   memset (szFilePath, 0, MAX_PATH);

   ofn.lStructSize = sizeof(OPENFILENAME);
   ofn.hwndOwner = hDlg;
   ofn.lpstrFile = szFilePath;
   ofn.nMaxFile = MAX_PATH;
   ofn.lpstrTitle = TEXT("Load Template File");

   if (GetOpenFileName (&ofn)) 
   {
      nRet = L_TwainOpenTemplateFile (g_hSession, &hFile, szFilePath, LTWAIN_TEMPLATE_OPEN_READ);

      if (nRet == SUCCESS)
      {
         L_UINT uIndex, uCapCount = 0;
         pTW_CAPABILITY ptwCapability = NULL;
         
         nRet = L_TwainGetNumOfCapsInFile (g_hSession, hFile, &uCapCount);
         if (nRet == SUCCESS)
         {
            for (uIndex = 0 ;uIndex < uCapCount ;uIndex ++)
            {
               nRet = L_TwainGetCapabilityFromFile (g_hSession, hFile, &ptwCapability, uIndex);
               if (nRet == SUCCESS)
               {
                  nRet = L_TwainSetCapability (g_hSession, ptwCapability, LTWAIN_CAPABILITY_SET);
                  if(nRet != SUCCESS)
                     return nRet;
               }
               else
               {
                  return nRet;
               }

               if (ptwCapability)
               {
                  GlobalFree (ptwCapability->hContainer);
                  GlobalUnlock(ptwCapability);
                  GlobalFree (ptwCapability);
               }
            }
         }
         else
            return nRet;

         nRet = L_TwainCloseTemplateFile (g_hSession, hFile);
         if(nRet != SUCCESS)
            return nRet;
      }
      else
         return nRet;
   }
   return SUCCESS; 
}