根据@saswanb的回复，这是Swift 4的版本:

var iphoneX = false
if #available(iOS 11.0, *) {
    if ((UIApplication.shared.keyWindow?.safeAreaInsets.top)! > CGFloat(0.0)) {
        iphoneX = true
    }
}

您需要根据实际需要对iPhone X进行不同的检测。

用于处理顶级(状态栏，导航栏)等。

class var hasTopNotch: Bool {
    if #available(iOS 11.0, tvOS 11.0, *) {
        // with notch: 44.0 on iPhone X, XS, XS Max, XR.
        // without notch: 24.0 on iPad Pro 12.9" 3rd generation, 20.0 on iPhone 8 on iOS 12+.
        return UIApplication.shared.delegate?.window??.safeAreaInsets.top ?? 0 > 24
    }
    return false
}

用于处理底部home指示器(标签栏)等。

class var hasBottomSafeAreaInsets: Bool {
    if #available(iOS 11.0, tvOS 11.0, *) {
        // with home indicator: 34.0 on iPhone X, XS, XS Max, XR.
        // with home indicator: 20.0 on iPad Pro 12.9" 3rd generation.
        return UIApplication.shared.delegate?.window??.safeAreaInsets.bottom ?? 0 > 0
    }
    return false
}

背景大小，全屏功能等。

class var isIphoneXOrBigger: Bool {
    // 812.0 on iPhone X, XS.
    // 896.0 on iPhone XS Max, XR.
    return UIScreen.main.bounds.height >= 812
}

注意:最终将其与UIDevice.current.userInterfaceIdiom == .phone混合 注意:此方法需要有一个LaunchScreen故事板或适当的launchimage

背景比例，滚动功能等。

class var isIphoneXOrLonger: Bool {
    // 812.0 / 375.0 on iPhone X, XS.
    // 896.0 / 414.0 on iPhone XS Max, XR.
    return UIScreen.main.bounds.height / UIScreen.main.bounds.width >= 896.0 / 414.0
}

注意:此方法需要有一个LaunchScreen故事板或适当的launchimage

用于分析，统计，跟踪等。

获取机器标识符并将其与文档值进行比较:

class var isIphoneX: Bool {
    var size = 0
    sysctlbyname("hw.machine", nil, &size, nil, 0)
    var machine = [CChar](repeating: 0, count: size)
    sysctlbyname("hw.machine", &machine, &size, nil, 0)
    let model = String(cString: machine)
    return model == "iPhone10,3" || model == "iPhone10,6"
}

要将模拟器作为有效的iPhone X包含在分析中:

class var isIphoneX: Bool {
    let model: String
    if TARGET_OS_SIMULATOR != 0 {
        model = ProcessInfo.processInfo.environment["SIMULATOR_MODEL_IDENTIFIER"] ?? ""
    } else {
        var size = 0
        sysctlbyname("hw.machine", nil, &size, nil, 0)
        var machine = [CChar](repeating: 0, count: size)
        sysctlbyname("hw.machine", &machine, &size, nil, 0)
        model = String(cString: machine)
    }
    return model == "iPhone10,3" || model == "iPhone10,6"
}

要包括iPhone XS、XS Max和XR，只需查找以“iPhone11”开头的型号:

return model == "iPhone10,3" || model == "iPhone10,6" || model.starts(with: "iPhone11,")

支持faceID

import LocalAuthentication
/// will fail if user denies canEvaluatePolicy(_:error:)
class var canUseFaceID: Bool {
    if #available(iOS 11.0, *) {
        return LAContext().biometryType == .typeFaceID
    }
    return false
}

使用简单的方法检测任何设备。像下面,

func isPhoneDevice() -> Bool {
    return UIDevice.current.userInterfaceIdiom == .phone
}

func isDeviceIPad() -> Bool {
    return UIDevice.current.userInterfaceIdiom == .pad
}

func isPadProDevice() -> Bool {
    let SCREEN_WIDTH: CGFloat = UIScreen.main.bounds.size.width
    let SCREEN_HEIGHT: CGFloat = UIScreen.main.bounds.size.height
    let SCREEN_MAX_LENGTH: CGFloat = fmax(SCREEN_WIDTH, SCREEN_HEIGHT)

    return UIDevice.current.userInterfaceIdiom == .pad && SCREEN_MAX_LENGTH == 1366.0
}

func isPhoneXandXSDevice() -> Bool {
    let SCREEN_WIDTH = CGFloat(UIScreen.main.bounds.size.width)
    let SCREEN_HEIGHT = CGFloat(UIScreen.main.bounds.size.height)
    let SCREEN_MAX_LENGTH: CGFloat = fmax(SCREEN_WIDTH, SCREEN_HEIGHT)

    return UIDevice.current.userInterfaceIdiom == .phone && SCREEN_MAX_LENGTH == 812.0
}

func isPhoneXSMaxandXRDevice() -> Bool {
    let SCREEN_WIDTH = CGFloat(UIScreen.main.bounds.size.width)
    let SCREEN_HEIGHT = CGFloat(UIScreen.main.bounds.size.height)
    let SCREEN_MAX_LENGTH: CGFloat = fmax(SCREEN_WIDTH, SCREEN_HEIGHT)

    return UIDevice.current.userInterfaceIdiom == .phone && SCREEN_MAX_LENGTH == 896.0
}

像这样叫，

if isPhoneDevice() {
     // Your code
}

struct ScreenSize {
    static let width = UIScreen.main.bounds.size.width
    static let height = UIScreen.main.bounds.size.height
    static let maxLength = max(ScreenSize.width, ScreenSize.height)
    static let minLength = min(ScreenSize.width, ScreenSize.height)
    static let frame = CGRect(x: 0, y: 0, width: ScreenSize.width, height: ScreenSize.height)
}

struct DeviceType {
    static let iPhone4orLess = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.maxLength < 568.0
    static let iPhone5orSE = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.maxLength == 568.0
    static let iPhone678 = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.maxLength == 667.0
    static let iPhone678p = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.maxLength == 736.0
    static let iPhoneX = UIDevice.current.userInterfaceIdiom == .phone && ScreenSize.maxLength == 812.0

    static let IS_IPAD              = UIDevice.current.userInterfaceIdiom == .pad && ScreenSize.maxLength == 1024.0
    static let IS_IPAD_PRO          = UIDevice.current.userInterfaceIdiom == .pad && ScreenSize.maxLength == 1366.0
}

为了快速解决问题，我喜欢这样:

let var:CGFloat = (UIDevice.current.userInterfaceIdiom == .phone && UIScreen.main.nativeBounds.height == 2436) ? <iPhoneX> : <AllOthers>

下面是Objective-C中需要的两个宏。

#define IS_IPHONE (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
#define IS_IPHONE_X (IS_IPHONE && [[[UIApplication sharedApplication] delegate] window].safeAreaInsets.top > 24.0)

用法:

if (IS_IPHONE_X) {
}

我希望它能帮助别人。