常用系统宏定义

1.区分系统是否为IOS6.0

#ifdef __IPHONE_6_0 

- (NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {

    NSLog(@"-------------");

    return UIInterfaceOrientationMaskPortrait;

}

#endif

2.区分系统版本

#if __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_3_2

//ToDo...

#endif

3.区分模拟器编译和真机编译

#if TARGET_IPHONE_SIMULATOR

    NSLog(@"iphoneSimulator");

#elif TARGET_OS_IPHONE

    NSLog(@"iphoneDevice");

#endif