为什么SetupDiEnumDeviceInterfaces返回值总是零？GetLastError()是ERROR_NO_MORE_ITEMS？谢谢

void CUsbtestDlg::OnInitUsb()
{
// TODO: Add your control notification handler code here
HDEVINFO HardwareDeviceInfo;
int j;
SP_INTERFACE_DEVICE_DATA deviceInfoData;
int NumberDevices;
HardwareDeviceInfo = SetupDiGetClassDevs(
(LPGUID)&GUID_CLASS_U_BULK,//{6bdd1fc6-810f-11d0-bec7-08002be2092f}
NULL,
NULL,
(DIGCF_PRESENT|DIGCF_INTERFACEDEVICE)
);
if( INVALID_HANDLE_VALUE == HardwareDeviceInfo)
{
lLastError = ::GetLastError();
AfxMessageBox("Get Device Class Failed");
}
else
{
AfxMessageBox("Get Device Class Success");
}

NumberDevices = 21;
deviceInfoData.cbSize = sizeof(SP_INTERFACE_DEVICE_DATA);
for(int i=0;i < NumberDevices;i++)
{
j = SetupDiEnumDeviceInterfaces(HardwareDeviceInfo,
0,
(LPGUID)&GUID_CLASS_U_BULK,
i,
&deviceInfoData);
}

if((!j)&&(::GetLastError() == ERROR_NO_MORE_ITEMS))
AfxMessageBox(" No Matched Device ");
else
AfxMessageBox(" Find Matched Device ");

PSP_INTERFACE_DEVICE_DETAIL_DATA functionClassDeviceData = NULL;
ULONG predictedLength = 0;
ULONG requiredLength = 0;
SetupDiGetInterfaceDeviceDetail(HardwareDeviceInfo,
&deviceInfoData,
NULL,
0,
&requiredLength,
NULL);
predictedLength = requiredLength;

functionClassDeviceData = (PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(predictedLength);
lLastError = ::GetLastError();
if(!SetupDiGetInterfaceDeviceDetail(HardwareDeviceInfo,
&deviceInfoData,
functionClassDeviceData,
predictedLength,
&requiredLength,
NULL))
{
lLastError = ::GetLastError();
AfxMessageBox("Get Device Path Failed");
//return 0;//INVALID_HANDLE_VALUE;
}
else
{
AfxMessageBox("Get Device Path Success");
}

HANDLE hDeviceHandle;
hDeviceHandle = CreateFile(
functionClassDeviceData->DevicePath,
GENERIC_READ|GENERIC_WRITE,
FILE_SHARE_READ|FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,0,
NULL
);
if(hDeviceHandle == INVALID_HANDLE_VALUE)
{
lLastError = ::GetLastError();
AfxMessageBox("Get Device Handle Failed");
}
else
{
AfxMessageBox("Get Device Handle Success");
}

char completeDeviceName[256] ="";
strcat(completeDeviceName,functionClassDeviceData->DevicePath);
strcat(completeDeviceName,"\\PIPE2");
hIntfHandle = CreateFile(
completeDeviceName,
GENERIC_READ|GENERIC_WRITE,
FILE_SHARE_READ|FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,
0,
NULL);
if(hIntfHandle == INVALID_HANDLE_VALUE)
{
lLastError = ::GetLastError();
AfxMessageBox("Get Interface Handle Failed");
}
else
{
AfxMessageBox("Get Interface Handle Success");
}

// return 0;
}

我也遇上了同样的问题.希望各位高手帮帮忙.
另外我发现调用SetupDiEnumDeviceInfo函数可以找到我的usb设备.
请问SetupDiEnumDeviceInfo与SetupDiEnumDeviceInterfaces有什么区别?是不是一个是device ?另一个是interface?但是device 与interface又有什么区别?

是的，因为我的设备已开始使用，通信还可以，我现在想测试一下。但是得不到设备的 句柄。还可能是其他问题吗？

确定你的设备和驱动正常工作/