代码：

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    self.title=@"屏幕旋转";
    
}
#pragma  mark -屏幕旋转
-(BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return (interfaceOrientation==UIInterfaceOrientationPortrait);
}
-(BOOL)shouldAutorotate
{
    return YES;
}
-(NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskPortrait;
}