public static extern Boolean SetupDiGetDeviceInterfaceDetail(
IntPtr hDevInfo,
ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData,
ref SP_DEVICE_INTERFACE_DETAIL_DATA deviceInterfaceDetailData,
UInt32 deviceInterfaceDetailDataSize,
out UInt32 requiredSize,
ref SP_DEVINFO_DATA deviceInfoData
);
public static extern Boolean SetupDiGetDeviceInterfaceDetail(
IntPtr hDevInfo,
ref SP_DEVICE_INTERFACE_DATA deviceInterfaceData,
ref SP_DEVICE_INTERFACE_DETAIL_DATA deviceInterfaceDetailData,
UInt32 deviceInterfaceDetailDataSize,
out UInt32 requiredSize,
ref SP_DEVINFO_DATA deviceInfoData
);
private string FindDevicePath()
{
var hidGuid = HidGuid;
var deviceInfoList = SetupApi.SetupDiGetClassDevs(ref hidGuid, null, IntPtr.Zero, DIGCF.DeviceInterface | DIGCF.Present);
if (IntPtr.Zero == deviceInfoList)
return null;
try {
for (uint i = 0; ; i++) {
var deviceInterfaceData = new SP_DEVICE_INTERFACE_DATA();
deviceInterfaceData.cbSize = (uint) Marshal.SizeOf(deviceInterfaceData);
if (!SetupApi.SetupDiEnumDeviceInterfaces(deviceInfoList, IntPtr.Zero, ref hidGuid, i, ref deviceInterfaceData))
break; // end of the list
var deviceInfoData = new SP_DEVINFO_DATA();
deviceInfoData.cbSize = (uint)Marshal.SizeOf(deviceInfoData);
if (!SetupApi.SetupDiEnumDeviceInfo(deviceInfoList, i, ref deviceInfoData))
continue;
const uint bufferSize = 1048;
var propertyBuffer = Marshal.AllocHGlobal((int)bufferSize);
try {
uint requiredSize;
uint propRegDataType;
if (!SetupApi.SetupDiGetDeviceRegistryProperty(
deviceInfoList, ref deviceInfoData, SPDRP.HardwareId, out propRegDataType,
propertyBuffer, bufferSize, out requiredSize)
) {
continue;
}
var deviceId = Marshal.PtrToStringAuto(propertyBuffer, (int) requiredSize);
if (String.IsNullOrEmpty(deviceId)
|| !deviceId.ToUpperInvariant().Contains(_deviceIdUpper)
) {
continue;
}
var deviceInterfaceDetailData = new SP_DEVICE_INTERFACE_DETAIL_DATA {
cbSize = IntPtr.Size == 8 ? 8 : (uint)(4 + Marshal.SystemDefaultCharSize)
};
var interfaceDetailOk = SetupApi.SetupDiGetDeviceInterfaceDetail(
deviceInfoList, ref deviceInterfaceData, ref deviceInterfaceDetailData,
SP_DEVICE_INTERFACE_DETAIL_DATA.BUFFER_SIZE, out requiredSize, ref deviceInfoData);
if (interfaceDetailOk)
return deviceInterfaceDetailData.devicePath;
}
finally {
Marshal.FreeHGlobal(propertyBuffer);
}
}
}
finally {
SetupApi.SetupDiDestroyDeviceInfoList(deviceInfoList);
}
return null;
}