我正在尝试连接到 USB GPS 设备。如果我通过 CreateFile WinApi 手动创建文件(使用设备管理器中指定的路径),我可以成功连接到设备。
但是,当我尝试通过枚举选择设备时,SetupDiGetDeviceInterfaceDetail 调用失败。
我的 C 代码可以正常工作,但我的 C# 翻译似乎无法正常工作。我尝试了许多变化,但结果基本相同。
有效的 C 代码
// Get enumerator handle for the specified ClassGuid
HDEVINFO theDevInfo = SetupDiGetClassDevs((GUID*)&GUID_DEVINTERFACE_GRMNUSB, NULL, NULL,
DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);
SP_DEVICE_INTERFACE_DATA theInterfaceData;
theInterfaceData.cbSize = sizeof(theInterfaceData);
// populate theInterfaceData which contains device class information
if (!SetupDiEnumDeviceInterfaces(theDevInfo, NULL, (GUID*)&GUID_DEVINTERFACE_GRMNUSB, 0, &theInterfaceData) &&
GetLastError() == ERROR_NO_MORE_ITEMS)
{
gHandle = 0;
return;
}
// This is normally used to obtain the device path information using theInterfaceData obtained above
bool initialized = SetupDiGetDeviceInterfaceDetail(theDevInfo, &theInterfaceData, NULL, 0, &theBytesReturned, NULL);
// theBytesReturned = 83
theDevDetailData =
(PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(theBytesReturned);
theDevDetailData->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);
bool initialized = SetupDiGetDeviceInterfaceDetail(theDevInfo, &theInterfaceData, theDevDetailData, theBytesReturned, NULL, &theDevInfoData);
C#
[DllImport(@"setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern Boolean SetupDiGetDeviceInterfaceDetail(
IntPtr hDevInfo,
ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData,
IntPtr deviceInterfaceDetailData,
UInt32 deviceInterfaceDetailDataSize,
out UInt32 requiredSize,
IntPtr deviceInfoData
);
[StructLayout(LayoutKind.Sequential)]
public struct SP_DEVICE_INTERFACE_DATA
{
public Int32 cbSize;
public Guid interfaceClassGuid;
public Int32 flags;
private UIntPtr reserved;
}
// Get enumerator handle for the specified ClassGuid
IntPtr theDevInfo = SetupDiGetClassDevs(ref ClassGuid, (DiGetClassFlags.DIGCF_PRESENT | DiGetClassFlags.DIGCF_DEVICEINTERFACE));
SP_DEVICE_INTERFACE_DATA DevInterfaceData = new SP_DEVICE_INTERFACE_DATA();
DevInterfaceData.cbSize = Marshal.SizeOf(DevInterfaceData);
initialized = SetupDiEnumDeviceInterfaces(theDevInfo, IntPtr.Zero, ref ClassGuid, 0,
ref DevInterfaceData);
// I assume The DevInterfaceData is populated correctly as it matches the C Code
// And I've compared the values in memory and they match
uint bytesReturned = 0;
initialized = SetupDiGetDeviceInterfaceDetail(theDevInfo, ref DevInterfaceData, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);
// I expect bytesReturned = 83 and initialized = true which is the value that is returned in the C Code
// Instead the value 162 is returned