UIDevice 获取设备相关信息备忘

使用方法：
[[UIDevice currentDevice]
systemVersion];//获取系统版本号
下面是UIDevice.h 中的一些信息，都可以按照上面的调用方式获取

@property(nonatomic,readonly,strong)
NSString    *name;             
// e.g. "My iPhone"
@property(nonatomic,readonly,strong)
NSString    *model;            
// e.g. @"iPhone", @"iPod touch"
@property(nonatomic,readonly,strong)
NSString    *localizedModel;   
// localized version of model
@property(nonatomic,readonly,strong)
NSString    *systemName;       
// e.g. @"iOS"
@property(nonatomic,readonly,strong)
NSString    *systemVersion;    
// e.g. @"4.0"
@property(nonatomic,readonly)
UIDeviceOrientation orientation
__TVOS_PROHIBITED;       // return current device orientation.  this will return UIDeviceOrientationUnknown unless device orientation notifications are being generated.

@property(nullable,
nonatomic,readonly,strong)
NSUUID      *identifierForVendor
NS_AVAILABLE_IOS(6_0);     
// a UUID that may be used to uniquely identify the device, same across apps from a single vendor.

@property(nonatomic,readonly,getter=isGeneratingDeviceOrientationNotifications)
BOOL generatesDeviceOrientationNotifications
__TVOS_PROHIBITED;
- (void)beginGeneratingDeviceOrientationNotifications
__TVOS_PROHIBITED;      // nestable
- (void)endGeneratingDeviceOrientationNotifications
__TVOS_PROHIBITED;

@property(nonatomic,getter=isBatteryMonitoringEnabled)
BOOL batteryMonitoringEnabled
NS_AVAILABLE_IOS(3_0)
__TVOS_PROHIBITED;  // default is NO
@property(nonatomic,readonly)
UIDeviceBatteryState          batteryState
NS_AVAILABLE_IOS(3_0)
__TVOS_PROHIBITED;  // UIDeviceBatteryStateUnknown if monitoring disabled
@property(nonatomic,readonly)
float                         batteryLevel
NS_AVAILABLE_IOS(3_0)
__TVOS_PROHIBITED;  // 0 .. 1.0. -1.0 if UIDeviceBatteryStateUnknown

@property(nonatomic,getter=isProximityMonitoringEnabled)
BOOL proximityMonitoringEnabled
NS_AVAILABLE_IOS(3_0);
// default is NO
@property(nonatomic,readonly)                           
BOOL proximityState NS_AVAILABLE_IOS(3_0); 
// always returns NO if no proximity detector

@property(nonatomic,readonly,getter=isMultitaskingSupported)
BOOL multitaskingSupported
NS_AVAILABLE_IOS(4_0);

@property(nonatomic,readonly)
UIUserInterfaceIdiom userInterfaceIdiom
NS_AVAILABLE_IOS(3_2);

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