[vc++]枚舉USB設備

#include <shlwapi.h>
#pragma comment(lib,"shlwapi.lib")
#include <setupapi.h>
#pragma comment(lib,"setupapi.lib")
/*
* 函數名稱: EnumUSBDev
* 函數功能: 枚舉設備			
* 參    數: 
*			acDevPath:				存放設備路徑
*			nDevNum:				設備數量
* 返 回 值: 成功返回TRUE,失敗返回FALSE
*/
BOOL CEnumDevDlg::EnumUSBDev(OUT char acDevPath[MAX_PATH][MAX_PATH], OUT int &nDevNum)
{
	//入參檢測
	nDevNum = 0;
	if (NULL == acDevPath)
	{
		return FALSE;
	}
	ZeroMemory(acDevPath, sizeof(acDevPath));
	BOOL								bRet = FALSE;
	SP_DEVICE_INTERFACE_DATA			DeviceInterfaceData;			// 保存設備接口信息
	DWORD								dwRequiredSize = 0;				// 得到詳細信息時需要的內存大小
	PSP_INTERFACE_DEVICE_DETAIL_DATA	pDeviceDetailData = NULL;		// 詳細信息
	HDEVINFO							hDeviceInfo;					// 設備信息集合的指針	
	GUID								InterfaceGUID = g_guidCdrom;
	DeviceInterfaceData.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
	
	//
	// 1.枚舉設備
	//
	int i = 0;
	hDeviceInfo = SetupDiGetClassDevs(
		&InterfaceGUID, 
		NULL, 
		NULL, 
		DIGCF_DEVICEINTERFACE|DIGCF_PRESENT);
	if (hDeviceInfo == INVALID_HANDLE_VALUE)
	{
		return FALSE;
	}
	while (1)
	{
		bRet = SetupDiEnumDeviceInterfaces(hDeviceInfo, NULL, &InterfaceGUID, i++, &DeviceInterfaceData);
		if(!bRet) 
		{
			break;
		}
		// 下面需要得到Interface的詳細信息
		// 先得到詳細信息需要的內存大小
		bRet = SetupDiGetDeviceInterfaceDetail(hDeviceInfo, &DeviceInterfaceData, NULL, 0, &dwRequiredSize, NULL);
		if(bRet)  
		{
			break;
		}
		// 爲詳細信息分配內存
		if(pDeviceDetailData) 
		{
			free(pDeviceDetailData);
			pDeviceDetailData = NULL;
		}
		pDeviceDetailData = (PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(dwRequiredSize);
		if(pDeviceDetailData == NULL) 
		{
			break;
		}
		
		// 得到Interface的詳細信息
		pDeviceDetailData->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);
		SP_DEVINFO_DATA DeviceInfoData;
		DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
		bRet = SetupDiGetDeviceInterfaceDetail(
			hDeviceInfo,
			&DeviceInterfaceData,
			pDeviceDetailData,
			dwRequiredSize,
			&dwRequiredSize,
			&DeviceInfoData);
		if ( !bRet ) 
		{
			break;
		}
		strcpy(acDevPath[nDevNum], pDeviceDetailData->DevicePath);
		nDevNum++;
	}
	if(pDeviceDetailData) 
	{
		free(pDeviceDetailData);
		pDeviceDetailData = NULL;
	}
	SetupDiDestroyDeviceInfoList(hDeviceInfo);
	return TRUE;
}

void CEnumDevDlg::OnButton1() 
{
	char acDevPath[MAX_PATH][MAX_PATH];
	int nDevNum = 0;
	EnumUSBDev(acDevPath, nDevNum);
	for (int i = 0; i < nDevNum; i++)
	{
		MessageBox(acDevPath[i], NULL, MB_OK);
	}
}