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LTwain::GetDeviceEventData

Summary

Gets information for a specific device event.

Syntax

#include "ltwrappr.h"

L_INT LTwain::GetDeviceEventData(pDeviceEvent)

Parameters

pTW_DEVICEEVENT pDeviceEvent

Pointer to a TW_DEVICEEVENT structure that references the required device event capability. This structure must be allocated and will be filled with data corresponding to the required capability to get.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

To get the CAP_DEVICEEVENT capability values, call LTwain::GetDeviceEventCapability function.

To set the CAP_DEVICEEVENT capability values, call LTwain::SetDeviceEventCapability function.

To reset the CAP_DEVICEEVENT capability value to the default, call the LTwain::ResetDeviceEventCapability function.

For information about TW_DEVICEEVENT, refer to the TWAIN specification.

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

float MyFix32ToFloat(TW_FIX32 * ptwFix) 
{ 
   float Floater = 0; 
   Floater = (float)ptwFix->Whole + (float)ptwFix->Frac / (float)65536.0; 
   return Floater; 
} 
 
L_INT LTwain__GetDeviceEventDataExample(LTwain * plTwain) 
{ 
   TW_DEVICEEVENT twDevice; 
   memset(&twDevice, 0, sizeof(TW_DEVICEEVENT)); 
   L_INT nRet = plTwain->GetDeviceEventData(&twDevice); 
   if (nRet != SUCCESS) 
      return nRet; 
 
   L_TCHAR szBuffer[MAX_PATH]; 
   memset(szBuffer, 0, sizeof(szBuffer)); 
   wsprintf(szBuffer, TEXT("Event = %d\nEvent Name  =%s\n"), twDevice.Event, twDevice.DeviceName); 
   MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
 
   if (twDevice.Event == TWDE_CHECKBATTERY) 
   { 
      wsprintf(szBuffer, TEXT("Battery Minutes = %d\nBattery Percentage = %d\n"), twDevice.BatteryMinutes, twDevice.BatteryPercentage); 
      MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
   } 
   else if (twDevice.Event == TWDE_CHECKPOWERSUPPLY) 
   { 
      wsprintf(szBuffer, TEXT("Power Supply =%d\n"), twDevice.PowerSupply); 
      MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
   } 
   else if (twDevice.Event == TWDE_CHECKRESOLUTION) 
   { 
      wsprintf(szBuffer, TEXT("XResolution = %f\nYResolution = %f\n"), MyFix32ToFloat(&twDevice.XResolution), MyFix32ToFloat(&twDevice.YResolution)); 
      MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
   } 
   else if (twDevice.Event == TWDE_CHECKFLASH) 
   { 
      wsprintf(szBuffer, TEXT("FlashUsed2 =%d\n"), twDevice.FlashUsed2); 
      MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
   } 
   else if (twDevice.Event == TWDE_CHECKAUTOMATICCAPTURE) 
   { 
      wsprintf(szBuffer, TEXT("Automatic Capture =%d\nTime Before First Capture =%d\nTime Between Captures = %d\n"), twDevice.AutomaticCapture, twDevice.TimeBeforeFirstCapture, twDevice.TimeBetweenCaptures); 
      MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
   } 
 
   return SUCCESS; 
}