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L_TwainAddCapabilityToFile

Summary

Adds a capability to a file.

Syntax

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainAddCapabilityToFile (hSession, hFile, pCapability )

Parameters

HTWAINSESSION hSession

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

pTW_CAPABILITY pCapability

Pointer to a structure that contains the capability to add.

Returns

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

Comments

In order to add a capability to a template file, the template file must first be opened for writing using L_TwainOpenTemplateFile. Opening the file for writing will create a new empty file. Capabilities are added to the file sequentially. When all capabilities have been added, save the file by calling L_TwainCloseTemplateFile. For more information on capabilities, refer to Getting and Setting Capabilities.

For more information on Template files, refer to Handling Template Files.

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.

Example

L_INT CALLBACK SaveCapsCB (HTWAINSESSION  hSession, 
                           L_UINT         uCap, 
                           pTW_CAPABILITY pCapability, 
                           L_VOID      * pUserData) 
{ 
   UNREFERENCED_PARAMETER(uCap); 
 
   L_INT nRet; 
   HTWAINTEMPLATEFILE hFile = NULL; 
 
   if (!pUserData) 
      return SUCCESS; 
 
   hFile = (HTWAINTEMPLATEFILE)pUserData; 
   if (!pCapability) 
      return SUCCESS; 
 
   if (!pCapability->hContainer) 
      GlobalFreePtr (pCapability); 
 
   nRet = L_TwainAddCapabilityToFile (hSession, hFile, pCapability); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   GlobalFree (pCapability->hContainer); 
   return SUCCESS; 
} 
 
L_INT TwainAddCapabilityToFileExample(HWND               hDlg, // Parent dialog handle 
                                                       HTWAINTEMPLATEFILE hFile, 
                                                       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.lpstrFilter = TEXT("LEAD TWAIN TEMPLATE\0*.ltt\0All Files\0*.*\0\0"); 
   ofn.lpstrDefExt = TEXT("ltt"); 
   ofn.lpstrTitle = TEXT("Save Template File"); 
   ofn.Flags       = OFN_PATHMUSTEXIST | OFN_OVERWRITEPROMPT | OFN_HIDEREADONLY; 
 
   if (GetSaveFileName (&ofn)) 
   { 
      nRet = L_TwainOpenTemplateFile (g_hSession, &hFile, szFilePath, LTWAIN_TEMPLATE_OPEN_WRITE); 
      if (nRet == SUCCESS) 
      { 
         nRet = L_TwainStartCapsNeg(g_hSession); 
         if(nRet != SUCCESS) 
            return nRet; 
         nRet = L_TwainEnumCapabilities (g_hSession, SaveCapsCB, LTWAIN_CAPABILITY_GETCURRENT, hFile); 
         if(nRet != SUCCESS) 
            return nRet; 
         nRet = L_TwainCloseTemplateFile (g_hSession, hFile); 
         if(nRet != SUCCESS) 
            return nRet; 
         nRet = L_TwainEndCapsNeg(g_hSession); 
         if(nRet != SUCCESS) 
            return nRet; 
      } 
      else 
         return nRet; 
   } 
   return SUCCESS; 
}