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L_TwainGetCapabilityFromFile

#include "lttwn.h"

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

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

Parameters

HTWAINSESSION hSession

Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession or L_TwainInitSession2 function.

pTW_CAPABILITY * ppCapability

Pointer to a pointer to a TW_CAPABILITY structure. This structure will be allocated internally.

L_UINT uIndex

Index of the capability to get from the file. This is a zero-based index.

Returns

Value	Meaning
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.

Functions

Topics

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;  
}

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