public static extern System.IntPtr zego_express_get_audio_device_list(ZegoAudioDeviceType device_type, ref int device_count);
 public static extern int zego_express_use_audio_device(ZegoAudioDeviceType device_type, [System.Runtime.InteropServices.InAttribute()][System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(ZegoUtil.UTF8StringMarshaler))] string device_id);