protected unsafe string RetrieveStringFromDevice(ushort index)
{
byte[] buffer = new byte[c_DeviceStringBufferSize];
byte *payload = null;
fixed(byte *p = buffer)
{
ushort wValue = (ushort)((ushort)((USB_STRING_DESCRIPTOR_TYPE << 8) & 0xFF00) | (ushort)(index & 0x00FF));
int read = m_winUsbDevice.Do_Control_Read_Transfer(ref buffer, USB_GET_DESCRIPTOR, wValue);
if (read != -1)
{
// null terminate the string
if (read > (c_DeviceStringBufferSize - 2))
{
read = c_DeviceStringBufferSize - 2;
}
p[read] = 0;
p[read + 1] = 0;
// skip first two characters
payload = p + 2;
}
}
return(payload == null ? null : new string((char *)payload));
}
