private static string GetDeviceName(IntPtr pDevInfoSet, SetupApi.SpDevInfoData deviceInfoData)
{
IntPtr hDeviceRegistryKey = SetupApi.SetupDiOpenDevRegKey(pDevInfoSet, deviceInfoData,
DICS_FLAG_GLOBAL, 0, DIREG_DEV, KEY_QUERY_VALUE);
if (hDeviceRegistryKey == IntPtr.Zero)
{
throw new Exception("Failed to open a registry key for device-specific configuration information");
}
var deviceNameBuf = new StringBuilder(256);
try {
uint lpRegKeyType;
uint length = (uint)deviceNameBuf.Capacity;
int result = RegQueryValueEx(hDeviceRegistryKey, "PortName", 0, out lpRegKeyType, deviceNameBuf, ref length);
if (result != 0)
{
throw new Exception("Can not read registry value PortName for device " + deviceInfoData.ClassGuid);
}
}
finally {
RegCloseKey(hDeviceRegistryKey);
}
string deviceName = deviceNameBuf.ToString();
return(deviceName);
}
/// <summary>
/// Obtains the serial ports and their descriptions using SetupAPI.
/// Prefered over the WMI implementation because it is significantly
/// faster, but requires admin access.
/// </summary>
private static IEnumerable <SerialPortInfo> GetPortsSetupApi()
{
var guids = new[] {
Guid.Parse(GUID_DEVINTERFACE_COMPORT2),
// Guid.AddToBuffer(GUID_DEVINTERFACE_COMPORT)
};
foreach (var guid in guids)
{
var guidCopy = guid;
IntPtr hDeviceInfoSet = SetupApi.SetupDiGetClassDevs(ref guidCopy, null, IntPtr.Zero,
SetupApi.DiGetFlags.Present);
if (hDeviceInfoSet == IntPtr.Zero)
{
throw new Exception("Failed to get device information set for the COM ports");
}
Int32 iMemberIndex = 0;
while (true)
{
var deviceInfoData = new SetupApi.SpDevInfoData();
deviceInfoData.cbSize = (uint)Marshal.SizeOf(typeof(SetupApi.SpDevInfoData));
bool success = SetupApi.SetupDiEnumDeviceInfo(hDeviceInfoSet, (uint)iMemberIndex, deviceInfoData);
if (!success)
{
// No more devices in the device information set
break;
}
var spiq = new SerialPortInfo {
Name = GetDeviceName(hDeviceInfoSet, deviceInfoData),
};
GetRegistryProperties(spiq, hDeviceInfoSet, deviceInfoData);
if (!string.IsNullOrEmpty(spiq.Name) && spiq.Name.Contains("COM"))
{
yield return(spiq);
}
iMemberIndex++;
}
SetupApi.SetupDiDestroyDeviceInfoList(hDeviceInfoSet);
}
}
private static void GetRegistryProperties(SerialPortInfo spiq, IntPtr hDeviceInfoSet, SetupApi.SpDevInfoData deviceInfoData)
{
var propertyBuffer = new StringBuilder(256);
const uint propRegDataType = 0;
uint length = (uint)propertyBuffer.Capacity;
bool success = SetupApi.SetupDiGetDeviceRegistryProperty(hDeviceInfoSet, deviceInfoData, (int)SetupApi.SPDRP.SPDRP_DEVICEDESC,
propRegDataType, propertyBuffer, length, out length);
//if (!success) throw new Exception("Can not read registry for device " + deviceInfoData.ClassGuid);
if (success)
{
spiq.Description = propertyBuffer.ToString();
}
propertyBuffer = new StringBuilder(256);
length = (uint)propertyBuffer.Capacity;
success = SetupApi.SetupDiGetDeviceRegistryProperty(hDeviceInfoSet, deviceInfoData, (int)SetupApi.SPDRP.SPDRP_HARDWAREID,
propRegDataType, propertyBuffer, length, out length);
if (success)
{
spiq.HardwareID = propertyBuffer.ToString();
}
}