程式碼

001       #include <stdio.h>

002       #include <windows.h>

003       #include <setupapi.h>

004       #include <devguid.h>

005       #include <regstr.h>

006    

007       int main( int argc, char *argv[ ], char *envp[ ] )

008       {

009           HDEVINFO hDevInfo;

010           SP_DEVINFO_DATA DeviceInfoData;

011           DWORD i;

012    

013           // Create a HDEVINFO with all present devices.

014           hDevInfo = SetupDiGetClassDevs(NULL,

015               0, // Enumerator

016               0,

017               DIGCF_PRESENT | DIGCF_ALLCLASSES );

018           

019           if (hDevInfo == INVALID_HANDLE_VALUE)

020           {

021               // Insert error handling here.

022               return 1;

023           }

024           

025           // Enumerate through all devices in Set.

026           

027           DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);

028           for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i,

029               &DeviceInfoData);i++)

030           {

031               DWORD DataT;

032               LPTSTR buffer = NULL;

033               DWORD buffersize = 0;

034               

035               //

036               // Call function with null to begin with, 

037               // then use the returned buffer size (doubled)

038               // to Alloc the buffer. Keep calling until

039               // success or an unknown failure.

040               //

041               //  Double the returned buffersize to correct

042               //  for underlying legacy CM functions that 

043               //  return an incorrect buffersize value on 

044               //  DBCS/MBCS systems.

045               // 

046               while (!SetupDiGetDeviceRegistryProperty(

047                   hDevInfo,

048                   &DeviceInfoData,

049                   SPDRP_DEVICEDESC,

050                   &DataT,

051                   (PBYTE)buffer,

052                   buffersize,

053                   &buffersize))

054               {

055                   if (GetLastError() == 

056                       ERROR_INSUFFICIENT_BUFFER)

057                   {

058                       // Change the buffer size.

059                       if (buffer) LocalFree(buffer);

060                       // Double the size to avoid problems on 

061                       // W2k MBCS systems per KB 888609. 

062                       buffer =(char *)LocalAlloc(LPTR,buffersize * 2);

063                   }

064                   else

065                   {

066                       // Insert error handling here.

067                       break;

068                   }

069               }

070               

071               printf("Result:[%s]\n",buffer);

072               

073               if (buffer) LocalFree(buffer);

074           }

075           

076           

077           if ( GetLastError()!=NO_ERROR &&

078                GetLastError()!=ERROR_NO_MORE_ITEMS )

079           {

080               // Insert error handling here.

081               return 1;

082           }

083           

084           //  Cleanup

085           SetupDiDestroyDeviceInfoList(hDevInfo);

086           

087           return 0;

088       }