L_TwainGetProperties

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainGetProperties (hSession, pltProperties, uStructSize, uFlags)

HTWAINSESSION hSession;	/* handle to an existing TWAIN session */
pLTWAINPROPERTIES pltProperties;	/* pointer to a structure */
L_UINT uStructSize;	/* size in bytes, of the structure pointed to by pBitmap */
L_UINT uFlags;	/* optional flags */

Gets the current or default values of the properties defined in the LTWAINPROPERTIES structure.

Parameter	Description
hSession	Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession function.
pltProperties	Pointer to a LTWAINPROPERTIES structure to be updated with the current or default properties. This must be a valid pointer for an LTWAINPROPERTIES structure.
uStructSize	Size in bytes, of the structure pointed to by pltProperties, for versioning. Use sizeof(LTWAINPROPERTIES).
uFlags	Flag that indicates the property values to get. Possible values are:
	Value	Meaning
	LTWAIN_PROPERTIES_GETCURRENT	[3] Get the current values.
	LTWAIN_PROPERTIES_GETDEFAULT	[4] Get the default values.

Returns

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

Comments

This function must be called after L_TwainStartCapsNeg is called and before L_TwainEndCapsNeg is called.

This function lets the user get information on the properties contained in the LTWAINPROPERTIES structure. It is a high-level alternative to getting capabilities using the L_TwainGetCapability or L_TwainEnumCapabilities functions. For more information on getting and setting TWAIN capabilities, refer to Getting and Setting Capabilities.

To set properties, use the L_TwainSetProperties function.

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_TwainStartCapsNeg, L_TwainEndCapsNeg, L_TwainSetProperties, L_TwainSetCapability, L_TwainGetCapability, L_TwainInitSession, L_TwainEndSession.
Topics:	Getting and Setting Capabilities
	TWAIN Functionality: Property Functions.

Example

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName


L_INT EXT_CALLBACK PropSetCB(HTWAINSESSION hSession,
                             L_UINT        uCap,
                             L_INT         nStatus,
                             L_VOID      * pValue,
                             L_VOID      * pUserData)
{
   UNREFERENCED_PARAMETER(hSession);
   UNREFERENCED_PARAMETER(uCap);
   UNREFERENCED_PARAMETER(nStatus);
   UNREFERENCED_PARAMETER(pValue);
   UNREFERENCED_PARAMETER(pUserData);

   // Do your error notification or place any other code here.

   return SUCCESS;
}

// Function to change the transfer mode to file

 L_INT TwainGetPropertiesExample(HTWAINSESSION g_hSession)
{
   L_INT nRet;
   LTWAINPROPERTIES twProps;

   // Initialize to zero
   memset (&twProps, 0, LTWAINPROPERTIESSIZE);

   // Get the current properties of the selected twain source
   nRet = L_TwainGetProperties (g_hSession, &twProps, sizeof(LTWAINPROPERTIES), LTWAIN_PROPERTIES_GETCURRENT);
   if (nRet != SUCCESS) 
      return nRet;

   // Change transfer mode to File
   twProps.DataTransfer.nTransferMode = TWSX_FILE;
   lstrcpy (twProps.DataTransfer.szFileName, MAKE_IMAGE_PATH(TEXT("Twain.bmp")));
   twProps.DataTransfer.nScanFileFormat = TWFF_BMP;
   
   // Set the new properties
   nRet = L_TwainSetProperties (g_hSession, &twProps, LTWAIN_PROPERTIES_SET, PropSetCB, NULL);
   if (nRet != SUCCESS) 
      return nRet;

   return SUCCESS;
}