使用宏定义判断设备型号

//判断是否为iPhone或ipad

#define UI_IS_IPAD              ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad)

#define UI_IS_IPHONE            ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)

//判断iPhone型号

#define UI_IS_IPHONE4          (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height < 568.0)

#define UI_IS_IPHONE5          (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 568.0)

#define UI_IS_IPHONE6          (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 667.0)

#define UI_IS_IPHONE6PLUS      (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 736.0 || [[UIScreen mainScreen] bounds].size.width == 736.0) // Both orientations

#define UI_IS_IOS8_AND_HIGHER  ([[UIDevice currentDevice].systemVersion floatValue] >= 8.0)

使用时直接判断 例如if(UI_IS_IPHONE4）