模拟器不识别人脸，但允许您模拟匹配和不匹配的人脸，如果您已从人脸ID中启用注册选项

 override func viewDidLoad() {
        super.viewDidLoad()
        localAuthentication()
    }



    func localAuthentication() -> Void {

        let laContext = LAContext()
        var error: NSError?
        let biometricsPolicy = LAPolicy.deviceOwnerAuthenticationWithBiometrics

        if (laContext.canEvaluatePolicy(biometricsPolicy, error: &error)) {

            if let laError = error {
                print("laError - \(laError)")
                return
            }

            var localizedReason = "Unlock device"
            if #available(iOS 11.0, *) {
                if (laContext.biometryType == LABiometryType.faceID) {
                    localizedReason = "Unlock using Face ID"
                    print("FaceId support")
                } else if (laContext.biometryType == LABiometryType.touchID) {
                    localizedReason = "Unlock using Touch ID"
                    print("TouchId support")
                } else {
                    print("No Biometric support")
                }
            } else {
                // Fallback on earlier versions
            }


            laContext.evaluatePolicy(biometricsPolicy, localizedReason: localizedReason, reply: { (isSuccess, error) in

                DispatchQueue.main.async(execute: {

                    if let laError = error {
                        print("laError - \(laError)")
                    } else {
                        if isSuccess {
                            print("sucess")
                        } else {
                            print("failure")
                        }
                    }

                })
            })
        }


    }
}