判断横屏
if ([UIApplication sharedApplication].statusBarOrientation == UIDeviceOrientationLandscapeRight || 
[UIApplication sharedApplication].statusBarOrientation == UIDeviceOrientationLandscapeLeft) {
    //当前横屏
} else {
   //当前竖屏
}

判断竖屏
if ([UIApplication sharedApplication].statusBarOrientation == UIDeviceOrientationPortrait || 
[UIApplication sharedApplication].statusBarOrientation == UIDeviceOrientationPortraitUpsideDown) {
    //当前竖屏
} else {
   //当前横屏
}