LTwain::GetCapabilityFromFile

#include "ltwrappr.h"

virtual L_INT LTwain::GetCapabilityFromFile (hFile, ppCapability, uIndex)

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
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.
< 1	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 LTwain::OpenTemplateFile 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:

$image\sqrblit.gif$ Free the container of the TW_CAPABILITY structure by a calling LTwain::FreeContainer function.

$image\sqrblit.gif$ Free the value referenced by the contents of the pptwCapability 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:	LTwain::OpenTemplateFile, LTwain::AddCapabilityToFile, LTwain::TemplateDlg, LTwain::GetNumOfCapsInFile, LTwain::CloseTemplateFile, LTwain::InitSession, LTwain::EndSession.
Topics:	Handling Template Files
	TWAIN Functionality: Capability Functions.

Example

class CMyTwain : public LTwain

{

//Create class here

};

// initialize session and call this function
void TestGetCapabilityFromFile(CMyTwain *MyClass, HWND hWndParent)
{
   OPENFILENAME ofn;
   L_INT nRet;
   HTWAINTEMPLATEFILE hFile;
   L_TCHAR szFilePath [MAX_PATH];

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

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

   if (GetOpenFileName (&ofn))
   {
      nRet = MyClass->OpenTemplateFile(&hFile, szFilePath, LTWAIN_TEMPLATE_OPEN_READ);

      if (nRet == SUCCESS)
      {
         L_UINT uIndex, uCapCount = 0;
         pTW_CAPABILITY ptwCapability = NULL;
         uCapCount = MyClass->GetNumOfCapsInFile(hFile);

         if (uCapCount > 0)
         {
            for (uIndex = 0 ; uIndex < uCapCount ; uIndex ++)
            {
               nRet = MyClass->GetCapabilityFromFile(hFile, &ptwCapability, uIndex);

               if (nRet == SUCCESS)
               {
                  nRet = MyClass->SetCapability(ptwCapability, LTWAIN_CAPABILITY_SET);
                }

               if (ptwCapability)
               {
                  GlobalFree (ptwCapability->hContainer);
                  GlobalFreePtr (ptwCapability);
               }
            }
         }
         MyClass->CloseTemplateFile(hFile);
      }
   }
}