好吧，这让我永远水力压裂，但我做到了！

Well, it's taken me fracking forever but I've done it!

我正在寻找的代码是

[UIDevice currentDevice].orientation;

这样就可以了

AVCaptureConnection *videoConnection = [CameraVC connectionWithMediaType:AVMediaTypeVideo fromConnections:[imageCaptureOutput connections]];
if ([videoConnection isVideoOrientationSupported])
{
    [videoConnection setVideoOrientation:[UIDevice currentDevice].orientation];
}

而且效果很好:D

呜呜呜！