Answer 1

Answer 2

我建议使用UIDeviceOrientationIsValidInterfaceOrientation(orientation)

它会告诉您它是否是有效的方向（有效的是横向或纵向，而不是FaceUp / FaceDown / UnKnown）。然后你就可以把它看作是它的肖像，如果它是未知的。

我就是这样做的：

if (UIDeviceOrientationIsValidInterfaceOrientation(interfaceOrientation) && UIInterfaceOrientationIsLandscape(interfaceOrientation)) {
    // handle landscape
} else {
    // handle portrait
}

Answer 3

[UIDevice currentDevice].orientation返回UIDeviceOrientation：

  

属性的值是一个表示当前值的常量   设备的方向。该值代表物理   设备的方向可能与当前不同   应用程序用户界面的方向。

您的getWidthAndHeightForOrientation函数采用UIInterfaceOrientation参数：

  

应用程序用户界面的方向。

这些类型虽然相关，却不是一回事。您可以使用self.interfaceOrientation从任何视图控制器访问当前的界面方向。 UIInterfaceOrientation有4个可能的值，UIDeviceOrientation有9：

typedef NS_ENUM(NSInteger, UIDeviceOrientation) {
    UIDeviceOrientationUnknown,
    UIDeviceOrientationPortrait,            // Device oriented vertically, home button on the bottom
    UIDeviceOrientationPortraitUpsideDown,  // Device oriented vertically, home button on the top
    UIDeviceOrientationLandscapeLeft,       // Device oriented horizontally, home button on the right
    UIDeviceOrientationLandscapeRight,      // Device oriented horizontally, home button on the left
    UIDeviceOrientationFaceUp,              // Device oriented flat, face up
    UIDeviceOrientationFaceDown             // Device oriented flat, face down
};

// Note that UIInterfaceOrientationLandscapeLeft is equal to UIDeviceOrientationLandscapeRight (and vice versa).
// This is because rotating the device to the left requires rotating the content to the right.
typedef NS_ENUM(NSInteger, UIInterfaceOrientation) {
    UIInterfaceOrientationPortrait           = UIDeviceOrientationPortrait,
    UIInterfaceOrientationPortraitUpsideDown = UIDeviceOrientationPortraitUpsideDown,
    UIInterfaceOrientationLandscapeLeft      = UIDeviceOrientationLandscapeRight,
    UIInterfaceOrientationLandscapeRight     = UIDeviceOrientationLandscapeLeft
};